Leap Motion is like a Kinect for your hands: it sits on your desk and senses hand motion above it. In LICHT, you use your index finger as a 3D mouse to lead a shiny ball through physics puzzles. Get Leap Motion here, currently $80 USD:
http://store-us.leapmotion.com/
If you already have one, get LICHT free here:
https://airspace.leapmotion.com/apps/licht-little-adventure/windows
And remember, ALT+O to activate Oculus Rift mode!
The video is recorded at 2560×1440, but in the Rift Development Kit 1 (DK1) I see it at only 1280×800.
Title music: Eric Steuer – “Bust That Rap Like Nobody’s Listenin’ (Dare 2 B Great remix)” / CC-BY