WinDirStat - WinDirStat is a disk usage statistics viewer and cleanup tool, inspired by KDirStat.
Diskdeleter - Diskdeleter is data removal software that helps protect your privacy by securely deleting data from your hard drive.
WizTree - WizTree quickly finds the files and folders using the most space on your hard drive. It scans the MFT (Master File Table) instead of crawling the entire disk which makes it very fast.
DriveStrike - Remote Wipe on any operating system in one place using DriveStrike. Data Breach Protection for your laptop, smartphone, and tablet.
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.
Wiperapp - Software build to meet all needs of companies dealing with erasing data on daily basis.