TidyUp! is a complete duplicate finder and disk tidiness utility.
With Tidy Up! you can search for duplicate files and packages; by the owner application, content, type, creator, extension, time modified, time created, name, label, visibility and date/age. You can also search by the tag, duration and bit installments of MP3 and AAC sound files and EXIF metadata*, search the contents of the iPhoto, Aperture, iTunes databases and Mail mailboxes, and synchronize deletions with iPhoto, Mail and iTunes.