The machine loads a series of GIFs via GIPHY's API and switches GIFs when you make a bucket. Super simple and super addictive.
The guts are a Raspberry Pi equipped with an IR beam-break sensor which is polled with synchronous modulation (because fluorescents) through an ADS1115 ADC. The Pi hosts a webserver that serves up the HTML display page, which can run on any device on the same network (in this case a Mac Mini) and gets its commands via websocket from the Pi sensing daemon.
The device also hosts an admin page that lets users change the search query used to load GIFs, which is a bit of an easter egg after somebody has been playing it for a while.
We're already exploding with ideas for v2 ... this thing is a slam dunk.
Images courtesy of Dark Igloo.