SequoiaView - SequoiaView is a featured rich application that comes with the visualization technique to provide you a single view of files and documents that are stored in your hard drive.
CleanMyMac X - Clean, protect and speed up your Mac
DiskBoss - A file manager with a focus on storage side of things: Monitoring, classing, storage, duplicate...
DaisyDisk - DaisyDisk is a disk analyzer tool for OS X that visualizes hard disk usage and allows to free up hard disk space.
DiskWave - DiskWave is a free utility to help you determine where most of your hard drive space is consumed.
Fossils - Find and clean out all your old unused files