CCleaner - CCleaner cleans, speeds up and frees up space on business endpoints.
TinkerTool - Tinker with the hidden settings of your Mac
BleachBit - When your computer is getting full, BleachBit quickly frees disk space.
Onyx by Titanium - This website provides operating system utilities for macOS
AVG PC TuneUp - Peak performance for your PC. Keeps it going for longer. - More Speed Turbo Mode
Cocktail - General purpose system modify/repair utility