FileLight.com

Duplicate Image Finder finds duplicate images on your computer. DIF compares images like you do: it compares 'what they look like' on the screen. DIF can match up resized images, rotated images, images with different filenames, or images in a different file format. DIF compares JPEG, BMP (bitmap), and GIF files. Once found, you can delete, move, and view your image files.