MacAllys $100 BTKeyMini is a small Bluetooth keyboard which fold ups and can can be carried in your bag. What makes this keyboard unique however, is MacAlley's claim that when it is released in March it will be compatible with the iPhone.
MacAlly confirmed this claim to MacWorld three times! "I was surprised by this claim, so I asked again to confirm. And then I asked a third time. MacAlly assured me I was understanding correctly."
This keyboard would be the first Bluetooth keyboard released that is operational with the iPhone.