Find duplicate pictures in your collection
dupeGuru Picture Edition is a tool to find duplicate pictures on your computer. Not only can dupeGuru PE find exact matches, but it can also find duplicates among pictures of different kind (PNG, JPG, GIF etc..) and quality. dupeGuru PE can also scan your iPhoto library.
NOTE: Even though dupeGuru PE is BSD, it as also Fairware , which has extra implications.