SDelete - Securely overwrite your sensitive files and cleanse your free space of previously deleted files using this DoD-compliant secure delete program.
Tune Sweeper - Show duplicates in your Music library. Automatically select which duplicates to keep and delete based on your preferences. Remove duplicates with one-click from your iTunes or Music app library.
Clean Master - Some users swear by it, some call it a glorified snake oil that does more harm than good. That can be said about any snake oil, but what specific brand of snake oil can boast almost a billion downloads around the world?
iTunes Duplicate Song Manager - iTunes Duplicate Song Manager with Folder Watch removes iTunes duplicates in Windows and Mac OS X.
CCleaner - CCleaner cleans, speeds up and frees up space on business endpoints.
SongGenie - SongGenie analyzes, identifies and repairs your mp3 tags and names.