Using cushion squarified treemaps, your hard drive contents are displayed graphically. The visualization is great to understand how your drive’s space is being used. Everytime I use a tool like this I end up deleting or compressing large files that are no longer used. WinDirStat is a source forge project that provides a Windows application. Cusion treemaps have been around for a while. Actually, WinDirStat is based on KDirStat, a previous project for X11 window managers. There is also a similar, yet simpler project, developed at the Technisch Universiteit Eindhoven, called Sequoia View.