generative modeling for Rhino
Hardware "sliders" (knobs) for Grasshopper. Arduino board inside. See this post for more info: (http://www.grasshopper3d.com/photo/hardware-remote-control-in-gh). Firefly connects between arduino and GH. The grey plastic case is 14 x 11 cm.
Tomasz Gancarczyk made one too: http://www.grasshopper3d.com/photo/knob-controller
and so did bingg http://www.grasshopper3d.com/photo/arduino-in-use