CCleaner (Crap Cleaner) is a freeware system optimisation, privacy and cleaning tool. It removes unused files from your system allowing Windows to run faster and freeing up valuable hard disk drive space. Additionally, it cleans traces of your internet activities such as your Internet history. Additionally it contains a fully featured registry cleaner. However, the best part is it’s fast (normally taking less than a minute to run) and contains NO Spyware or Adware!
Thanks to Matsuda for the update.