RoboCopy - Robocopy is a free file copy tool that is included with the Microsoft Windows operating system. It allows one to construct complicated instructions to move, or copy files.
WinDirStat - WinDirStat is a disk usage statistics viewer and cleanup tool, inspired by KDirStat.
Ultracopier - SuperCopier replaces Windows explorer file copy and adds many features: Transfer resuming, transfer...
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.
FastCopy - FastCopy is the fastest copy, delete, & sync software on Windows.
TreeSize - TreeSize tells you where precious disk space has gone to.