Track your hard drive usage with WinDirStat
WinDirStat lets you create art from your hard drive. But that's really a side effect of its primary purpose, which is to provide you with information about your disk use. We first told you about this free application back in 2005. But even though the program hasn't been updated since last year, it runs just fine on Windows Vista.
While Windows Explorer lets you order files in a folder from largest to smallest or vice versa, it's pretty much useless when it comes to figuring out why your hard drive is almost full. Not that you really need a program to tell you that you've been spending too much time on iTunes (or BitTorrent), but WinDirStat can help you track down large files on your PC.
Each chunk of colored lights represents a folder on your computer. Or if you can do without the visuals, you can just focus on the top window that shows you where your largest files are.