This is the first cute, high-tech, electronic Cat Door System I’ve seen since the Flo Control Project.
Flo Control took an image of the cat’s head and analyzed it to see if the programmer’s cat Flo was carrying prey. If she was, the cat door would not open. Voila! No more feathers and mouse bits or lizards or snakes in the house. It was quite a clever bit of programming that found its way into some image-recognition systems.
The Twitter Cat Door uses RFID tags in the cats’ collars, servomotors, and a camera to keep strange cats out of the house, but also snap pictures of the cats entering and leaving. The system keeps a log of the cats’ movements and combines it with randomly selected reasons to post the cats’ comings and goings on Twitter (as GusAndPenny) and Twitpic.
The cats do a lot of going in and out.

At night and on dim days, the reflection of a clock shows up:
