Disk Investigator doesn't simply help you find lost files. It also helps you uncover plenty of information about the contents of your hard drive. When you launch the free application, it quickly analyzes your disk and presents you with a list if information about its size and contents.

The information will likely fly over the head of anyone but the geekiest of geeks: It's all about clusters, cluster size, zones, and more. And that's just the tip of the iceberg, as the main window displays strings of letters and numbers that are completely indecipherable to most humans.

This information is valuable to anyone looking for lost files because of its very nature: Disk Investigator bypasses the operating system and reads the "raw drive sectors." This allows you to enter a search string and have Disk Investigator comb your drive for that missing file.

Disk Investigator's scans are thorough, and as such they take a long time—in some cases, several hours. And the results can be just as difficult to decipher as the rest of the information the application presents. But digging through those results can be worth your time, as Disk Investigator proved capable of finding some valuable files. It managed to track down both a video file I'd deleted and an email attachment I'd edited and forgotten to save.

Disk Investigator can be confusing to use and time-consuming, but in the end, its results are worth it.