If you’re as fumbly with the camera as I am, you might download several of the same images to iPhoto over and over again before finally deleting them off your camera. Thankfully you don’t have to delete whole albums to remove those well hidden duplicates: you can simply run Duplifinder from Haystack Software. Duplifinder runs as its own app, closing and launching iPhoto when it’s necessary to accomplish one of its two tasks. Firstly, Duplifinder will scan your iPhoto library before presenting you with the option to dump duplicates into their own folder, or deleting them via iPhoto’s trash. You’re shown both the original and duplicate images before you commit to any rash decisions (extras of those ex-girlfriend photos are handy to have on hand), and you can bet you’ll use the software often if you’re taking photos all day long.
The app is only $7, and works with iPhoto ‘08, ‘09, and ‘11.