CleanMyMac X - Clean, protect and speed up your Mac
CleanMem - CleanMem keeps memory use in check on the system without the memory being pushed to the page file.
MacKeeper - The new MacKeeper app delivers multilayered protection from malware, online threats, and identity theft & Mac performance optimization. Learn what is MacKeeper.
Fossils - Find and clean out all your old unused files
MacCleaner Pro - MacCleaner Pro is a bundle of 6 apps to clean up disk space and speed up Mac.
DaisyDisk - DaisyDisk is a disk analyzer tool for OS X that visualizes hard disk usage and allows to free up hard disk space.