Rarely do we look at an accessory and say that it makes little sense, but United SGP's Metal Skin for iPhone 3G ($22) initially appears to be pretty close. Clearly adapted from a product developed for a different cell phone, the Metal Skin is an adhesive sticker set designed to add additional metallic accents to the iPhone 3G in your choice of silver, gold, blue, red, or black colors. The problem is that most of the stickers included here can't actually…
