Line 6 Mobile Keys 25 Controller
For any musically-inclined techies, there's the Line 6 Mobile Keys 25 Controller, which turns any tablet, PC or Mac into a mini-piano.
Equipped with 25 full-sized, velocity-sensitive keys, this portable keyboard is compatible with any CoreMIDI music apps, along with digital audio workstations such as GarageBand. It's bus-powered, too, so there's no need for batteries or an adapter.
The Line 6 Mobile Keys 25 Controller sells for $150 on Line 6's website.