The Drive Space Mapper is a tool that shows which files/folders are taking up the space on a disk drive. You select a drive (or folder) to be scanned, and get information which folders/files take up the most space. This information can be visualized as a TreeMap (see screenshot below), Pie chart, Top 10 or a regular list.
You can go to the download page here to get the application. Current version is 0.9.2
Although it is not a 1.something version yet, the main reason for not a full release is that I haven't written a help file yet. I don't consider a program fully ready until it has at least a rudimentary help file. Other than the help file it is works correctly as far as I know. Hint: if you do find something that doesn't work (or not as expected), let me know. The email address is at the bottom of this page.
Some features: