KleanSweep is a wonderful application to help you clean up the unnecessary files from your computer. KleanSweep searches and finds Empty files and directories, Broken Symlinks, Backup files, Orphaned Files, Dead menu entries, Obsolete thumbnails and Duplicated files.
Using KleanSweep is as straight forward as choosing what you are searching for and selecting the directory to search. The files that match your criteria are searched and listed for you to remove from your system.
Other similar project include FDupes and FSlint for Linux & Duplicate File Finder (DupFiles) for Windows