CCleaner is a popular tool that automatically find the unused files on the system make it run faster and free up the hard disk space. It also allows the users to clean the traces of online activity. CCleaner was only available for Windows but now it has been released for Mac OS.
It is currently available in beta version. It only provides basic features as compare to Windows version. In the beta release, it supports only Firefox and Safari cleaning with other options to clean Trash, Temporary Folder, Recent Files and Servers.