Blocks is a tiny synth system that fits in a laptop bag but looks like a ton of fun, with various modules that click together, weird touch- and pressure-sensitive rubbery keys and pads, and various "control" blocks for looping, recording, sequencing, and MIDI/USB connections to other gear.
Roli Blocks [Amazon]
They also sell a range of keyboard controllers using the same design. Even the two-octave models are awfully expensive; I don't even want to know how much the "grand" model is.
https://www.youtube.com/watch?v=P2syqXx97LE
