A Japanese company called Factron has released a metal iPhone case complete with a mount for conversion lenses. The Quattro for iPhone case is currently only compatible with the iPhone 3G - a modified version for the iPhone 3Gs is currently in the making. The conversion lenses on offer include two close-up optics, a superwide converter and even a circular fisheye. The case itself costs a whopping 19,600 yen, but the lenses themselves are available for 1,700 to 5,300 yen.
Website: Quattro for iPhone (in Japanese)
Illustrations sourced from manufacturer’s website
Click on a thumbnail to see the full version.