WinDirStat - WinDirStat is a disk usage statistics viewer and cleanup tool, inspired by KDirStat.

N2WS Cloud Protection Manager - N2WS is the leading Enterprise-class disaster recovery, and backup solution specifically made for Amazon EC2 servers.

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.

VSquare - Vsquare is a Vmware and Hyper-V-based data protection, disaster recovery, and business continuity solution that provides businesses with a complete, affordable solution for protecting their data and ensuring continuity in the event of a disaster.

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.

CloudEndure - CloudEndure provides cloud migration and cloud disaster recovery for any application.