Trash it! 

Trash it! can uninstall programs as well as delete unneeded files such as windows temp files (*.tmp) etc. Features such as Automatic Setup Detection make it very user friendly. It even comes with a scheduler that runs in your system tray.
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Windows System Optimizer 

Windows System Optimizer is an optimizer software that speeds up your system, giving you maximum performance. It includes cleanup tools for Windows system.
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Registry Repair 

Registry Repair is an advanced registry cleaner for Windows that allows you to safely scan, clean, and repair registry problems.
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WINSWEEP 

Surf anonymously. Popup-blocker for the IE. Destroy Surfing Traces. Daily check for viruses and worms! Deletion of the history of the IE. Deletion of the url-list of the IE. Cookies will be deleted completly. Ad-Blocker. Anonymous Email.
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ByteSweeper 

ByteSweeper removes unused and temporary files from your system - allowing it to run faster, more efficiently and giving you more hard disk space. The best part is that it's fast!
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