Baku allows you to search for system registry errors and unneeded files that can be safely removed.

Features:

Deletes empty folders, 'History' folder contents, 'Recent documents' folder contents, 'Temp' folder contents, temporary internet files, cookies.
Searches Windows log files, shortcuts to missing files and folders and user specified file types.
Registry scan removes unused and obsolete keys, including ActiveX/COM, Application Paths, Fonts, Help files, Icon files, Sound files, Uninstall Programs and Windows Installer.
The registry is automatically backed up before any changes are made.
Implements the standard DOD 5220.22-M, to give you confidence that once deleted, your file data is gone forever (if Eraser is installed it will be used instead).
Clears MRU lists from many applications including Media Player, eMule, Firefox, Opera, Internet Explorer, Microsoft Office, Nero, Adobe Acrobat, WinRAR, WinAce, WinZip, etc.
Compacts the registry hives to the minimum size possible.
Heuristic based scanning of applications MRU lists.
Ability to backup and restore the entire system registry.
Backup and restore system device drivers.