WinDirStat - WinDirStat is a disk usage statistics viewer and cleanup tool, inspired by KDirStat.
RocketDock - RocketDock is a Mac OS X dock clone.
TreeSize - TreeSize tells you where precious disk space has gone to.
ObjectDock - ObjectDock is the most popular animated dock for Windows.
SpaceSniffer - SpaceSniffer is a freeWare (donations are welcome) and portable tool application that lets you understand how folders and files are structured on your disks.
Cairo-Dock - Cairo-Dock / GLX-Dock 3. 4 is now available. Cairo-Dock 3. 4 is finally released! One year after the 3.