I recently came across a handy tool that I thought I would share. It is called
SpaceMonger. It gives a very nice graphical display of exactly where all of your data is being stored on your hard drive. Most of the time it is easy enough to know where to go to free up space, however, recently I had a drive that I had trimmed most of the fat off of and I still needed to clear up more space. This tool helped me to find some "hidden" cache directories that windows had storing 6GB+ of data that was not needed. Anyway, worth a shot if you are having trouble figuring out where to find the large chunks of useless space being used on your hard drive.