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 on to the back of the phone.
The case itself is made of aircraft-grade duralumin, which lends it 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 ¥19,600 (£130) 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.