Windows only: Portable utility Mute on Lock turns off your system speakers whenever you walk away and lock your workstation, but it also provides a quick shortcut key for toggling your speakers on or off.

Once you've downloaded and launched the no-installation-required utility, your speakers will turn off immediately after pressing the Win+L shortcut key to lock your workstation, and then turn back on once you've unlocked your PC. If you head into the settings page, you can set up a custom shortcut key to mute or unmute the sound, or customize what the tray icon does. Definitely a handy utility for those of us that lock our workstations religiously, and it doesn't take up a lot of resources either.

Mute on Lock is a free download for any version of Windows, though readers should note that you might have to use the Windows Compatibility Mode feature set to Windows XP to get it to work properly on Windows 7.

Windows only: LookInMyPC generates a complete report of what's going on in a computer—from hardware to software, and everything in between. After playing around with it, this writer wouldn't start troubleshooting a PC without it. I'm not kidding.

Whether you're a tech guru who knows your way around your computer better than the company that built it, or a novice just getting acquainted with your system, LookInMyPC is a free app you'll want to download and run at least once, even before you need its diagnostic help. It's like a big verbal X-Ray of your PC, detailing everything from the brand of network adapter you have to the number of user accounts on your system.

Everything that a LookInMyPC report generates can already be found in your computer's accessible files if you know where to look, but this utility makes it so much easier. Just open the system inspector and tick the boxes to select all or some of the more than 40 diagnostic checks you want it to perform. Seconds later, you'll have a long report outlining every detail LookInMyPC ferreted out for you. Stash it in a drawer with your computer's owner's manual for a fast and handy reference sheet the next time you need to know what brand sound card you have or what the specs are on your processor.

LookInMyPC is also a great tool for diagnosing computer issues, especially if you're troubleshooting an unfamiliar computer. Instead of spending time poking around your uncle's PC to figure out basic system information, just generate a general report with memory and operating system information, then get down to business. Once you have a feel for what issues you're trying to correct, you can generate more specific reports like Registry Run Entries or Firewall Info. LookInMyPC even gives you data on Windows updates, recent System Restores, and the default email client.

The utility won't make any changes to your system at all, no matter what issues it identifies. The reports open up in a browser window and many of the results—like system hardware vendors and application names—are hyperlinked so you can quickly Google-search things you don't recognize.

One really nice touch that's included in this app is the ability to generate a report that automatically turns itself into a ZIP file and emails it to the address of the user's choice. That's a huge help when you get a distress call from a relative who wants you to troubleshoot his computer remotely.

LookInMyPC is designed to work with Windows 2000, 2003, XP, and Vista, but we ran it on Windows 7 with no issues. Pair this app with screencasting webapp ShowMeWhatsWrong and you'll be the neighborhood PC go-to person in record time. What apps and tools are already in your troubleshooting toolkit? Know of a similar solution, like previously mentioned SIW? Tell us in the comments.

Windows: Ever download a movie from—oh, I don't know—some far-reaching nether-region of the internet, and when your download finishes realize the video is split into multiple parts? AVI Joiner quickly combines those split videos in just a few clicks.

Using it could not be easier. Just run the app (AVI Joiner.exe), drag and drop the files you want to join into the Files to be joined pane, make sure they're in the correct order, and click the Run AVI Joiner button. The app will ask you where you want to save the joined video (name it and make sure to add the .avi extension to the end), then sit back as it fires up a command line and starts the joining process. I joined a couple of 700MB files into a 1.4GB video in roughly a minute.

This awesome little app was built courtesy of the Lifehacker Coders group over at the Productive Geek forums. You can currently grab the download hosted over at drop.io here. We reached the download cap—get the ZIP here instead. (For a portable version, grab the AVI_Joiner.zip file; if you want an installer, grab the setup.exe and install.nsi files. Make sure you grab the newest versions, and if we happen to hit a bandwidth cap at drop.io, be sure to let me know.)

AVI Joiner is a free, open-source application for Windows only.

Windows only: Spyware removal tool SUPERAntiSpyware has finally released an official portable version of their application, and, just like the installed version, it easily removes most infections on your PC in a single swipe.

Once you've downloaded the application, the first thing you'll probably notice is the weird filename—each time you download it you'll be given a random filename, because most of the worst malware will prevent you from opening or installing any known malware removal tools. You'll be prompted for the language and a start screen, and then you can scan the infected PC immediately—the latest definition updates come with the download.

We've featured SUPERAntiSpyware before as one of the best malware removal tools, but the addition of a portable version makes it well worth a look for anybody with a machine infected with spyware. I've personally used this tool a dozen times to remove many different fake antivirus infections like Antivirus Live, and it's never let me down.

SUPERAntiSpyware Portable is a free download for Windows users. Click the link for the download, or check out the full screenshot tour over at How-To Geek.

Windows only: The newest version of the popular Avast Antivirus is finally available for download. It's lighter, faster, and more feature-filled than ever, bringing a new behavior shield, heuristics engine, and code emulator to keep you protected at all times.

Apart from its far easier-to-navigate interface, Avast has a few new features that make it hard to turn down. Its new code emulator can emulate a suspicious executable's code, isolated, for use in its new heuristics engine, designed to detect malware that would otherwise be undetectable with normal definitions—in other words, spotting malware by learning what the code does. If you use the pro version, you also get their new sandboxing feature for even further protection.

Apart from the new features, Avast has also lowered scanning times as well as the resources necessary to scan and update—a common issue with antivirus programs that are always running in the background. If you're already an Avast lover (and many of you are), you can either wait for the program to update itself in the near future or go download 5.0 straight from Avast. If you've tried Avast and turned it down before, it may be worth another look—you may find that its former cons (such as the difficult-to-use GUI and resource use) are now more up to your standards.

Avast Antivirus is a free download, Windows only.

Windows only: The newest version of the popular Avast Antivirus is finally available for download. It's lighter, faster, and more feature-filled than ever, bringing a new behavior shield, heuristics engine, and code emulator to keep you protected at all times.

Apart from its far easier-to-navigate interface, Avast has a few new features that make it hard to turn down. Its new code emulator can emulate a suspicious executable's code, isolated, for use in its new heuristics engine, designed to detect malware that would otherwise be undetectable with normal definitions—in other words, spotting malware by learning what the code does. If you use the pro version, you also get their new sandboxing feature for even further protection.

Apart from the new features, Avast has also lowered scanning times as well as the resources necessary to scan and update—a common issue with antivirus programs that are always running in the background. If you're already an Avast lover (and many of you are), you can either wait for the program to update itself in the near future or go download 5.0 straight from Avast. If you've tried Avast and turned it down before, it may be worth another look—you may find that its former cons (such as the difficult-to-use GUI and resource use) are now more up to your standards.

Avast Antivirus is a free download, Windows only.

Windows only: Planning an upgrade soon? Save yourself the web searches for your specs and download Speccy. Speccy does a quick scan of your machine and gives you a complete rundown of every piece of gear that's in your computer.

Upon first glance, Speccy seems like something that's only attractive to power users, but it can be useful for anyone. When the Device Manager doesn't give you enough information about what kind of RAM you have (say, if you're looking to upgrade), Speccy will give you all the information you could possibly need, including the RAM type, how much you currently have, and even the number of slots used so you can buy with confidence.

You can view your computer's information in a brief summary (as shown), or click on any of the categories for a very, very detailed report. Speccy gives you detailed information for CPU, motherboard, graphics, hard drives, optical drives, and audio, all so you don't have to go searching somewhere else to find out what you have. In addition, it also gives you real-time information on things like bus speed, DRAM Frequency, and temperature, to name a few.

We've featured one or two different tools like this in the past, but thus far, this is the cleanest and most detailed one we've used yet. Speccy is a free download, Windows only.

Windows only: Portable application NirLauncher bundles 100+ of the best NirSoft utilities into a single launcher window, and even allows you to add your own utilities to make a killer flash drive toolkit.

Once you've downloaded the zip file, you can extract the contents into a new folder on your desktop or flash drive, and then launch the NirLauncher.exe application from that folder, which will give you quick access to the 100+ NirSoft utilities included in the package.

It's important to note that because of the system-tweaking, hacking nature of the NirSoft utilities, they sometimes come through as a false positive on your anti-malware utility—but that doesn't mean that they are infected with a virus. Depending on the type of system protection that you have installed, you might have to remove the files from the quarantine folder in order to use all of the utilities.

Tweaking the Launcher

You can edit the included NirSoft.nlp file in a text editor to add or remove the utilities that you prefer—or you can even create a new .NLP file with your own customized settings. Just make sure to use relative paths to the executable files to make sure that they will be portable when you put it onto your flash drive.

The NirSoft blog even provides a launcher file for the suite of awesome, portable, system-tweaking tools from SysInternals—simply download the launcher file and extract all of the SysInternals applications into a folder, and then use the Launcher -> Add Software Package menu to add the entire group into the application. Once you've got them there, you can switch between the NirSoft and SysInternals groups with the F3 key, or through the Launcher menu.

NirLauncher is a free download for Windows only. What applications would you include in your own portable flash drive toolkit? Tell us in the comments. Thanks, Scott!

Windows only: When you upgrade your video card—or even just the drivers—the old version leaves settings and registry entries cluttering up your system—but you can clean them up.

Driver Sweeper works by removing all the extra stuff that the driver uninstaller leaves behind—so you'll need to first uninstall the video card, motherboard, or sound card drivers, and then run the utility to remove all the extra traces. Once you've done so (and rebooted), you can proceed with installing the newer drivers. It's one of those really useful utilities that isn't necessary for most people—in fact, not recommended for the less tech-savvy—but a critical tool that I've used whenever I do an upgrade.

Driver Sweeper is a free download for Windows only. If you have a device that isn't supported, or want to remove drivers the built-in Windows way, I've previously written an article on how to boost performance by removing old drivers after upgrading to new hardware.

Windows only: Free application MetatOGGer is an advanced MP3 (and OGG Vorbis, FLAC, Speex, Musepack, Windows Media, WavPack, and Monkey's Audio) tag editor that can automatically tag your music by creating audio fingerprints and comparing them with online database, MusicBrainz.

(Click the image above for a closer look.)

And while MusicBrainz already has its own dedicated application for this (the previously mentioned Picard), we've always found Picard to be a little clunky. MetatOGGer, on the other hand, seems quite a bit more user friendly. Likewise, MetatOGGer can automatically search out and add lyrics to your tags from web site LyricWiki.

This one didn't make our list of the six best MP3 tagging tools, but then again, we didn't even know it existed. And while it may not be as efficient as something like MP3Tag (our Hive Five winner), it does show a lot of promise.

MetatOGGer is freeware, Windows only, requires .NET 3.5 SP1. If you give it a try, let's hear how it worked for you in the comments.