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.