Tidy Up is a full-featured 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 Photos, iPhoto, Aperture, iTunes, iPod databases, and Mail mailboxes; and synchronize deletions with iPhoto, Mail, and iTunes. … and etc