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.