There's also Peter R's Sigsafe: https://bitcointalk.org/index.php?topic=610453.0
It looks like it's even easier to use than a trezor and also cheaper. It communicates via NFC and the same device can be used with a mobile or a vendor terminal. As I see it, the answer to the question "How do I get bitcoins to and from that thing?" would be as simple as "Just tap it to your mobile!". However, it's still in development.