More Space Sanitizer 

Safely reclaim and sanitize disk space by deleting duplicates and file hogs. Identifies duplicate files, file hogs, folder hogs, temporary files and more.
morespace diskspace free disk space disk utility sanitize

Wipe It 

Sanitize your hard drive, flash drive, zip drive and more... Don't let your important data fall into the wrong hands. Sanitizing a drive using Wipe It ensures that deleted files can never be recovered - nothing will come back to haunt you.
wipe-it wipe it wipeit sanitize secure clean wipe drives

DriveScrubber 

DriveScrubber allows you to securely wipe away data left on your drives before donating, reselling, recycling, or even cleaning up after virus attacks. It's fast and easy to use, and works with ANY PC, and wipes ANY drive, regardless of its format.
wipe disk drive data erase delete clean sanitize undelete unformat format drivescrubber iolo