This is a demo of a coffee table music controller made with Reactivision. Details below.

via ingiacapoeira:

reactivision and puredata, im tracking a marker stuck under the mug with a webcam placed under the table… from where im sitting, up/down is sample pitch, left right switches between samples and the mug angle = retrigger X2 (clockwise) or X4 (ant-clockwise). get the pd patch at my homepage cheapthrills.toile-libre.org