Disk scrubber. Security and freespace
When your computer is getting full, BleachBit quickly frees disk space. When your information is only your business, BleachBit guards your privacy. With BleachBit you can free cache, delete cookies, clear Internet history, shred temporary files, delete logs, and discard junk you didn't know was there. Designed for Linux and Windows systems, it's now available for Mac OS X.