Winkekatze
The Idea came up at CCCamp 2015. A Worldwide Web of Winkekatzen! What an awesome Idea.
We bought a cheap Winkekatze of off eBay. Its actually a quite hackable cat, i can recommend it. We made a simple controller for it and a friend wrote the Software.
Notes
We used an ESP01, which is usually the cheapest available. But any other should work fine. Actually, any other should be finer, as the ESP01 is rather finicky to program.
We used an LM1117 regulator. Dont try the smaller versions, they wont suffice. Better use a buck converter or LM317. We had lots of trouble with ESP due to insufficient power suplkies.