You can find plenty of iPhone applications that use software to create effects for the built-in camera, but the Quattro iPhone 3G Case, made by Japanese company Factron, is one of the first hardware add-ons to actually mount an aftermarket lens onto the front of the phone.
The case itself is made of aircraft grade duralumin for durability and a sexy polished-silver finish. The backside of the case is covered with supple calf leather for the highest in dead-animal quality, but the external lenses are the real stars and include fish-eyes, macros, wide angles, superwide conversions, and more. Put them together and the case and lenses turn your iPhone into a futuristic Victorian steampunk Transformer.
The Quattro case sells for $200 on the Factron Web site, and unfortunately you have to shell out even more for each custom lens.
Click through the slideshow below for more pictures of the case and lenses.