No, not building a cat. My house now holds three (3) cats. two are bossy, one is incredibly pushy, and will eat the other cats' food. The one that's mine is a pushover and may not get all his food. My wife and I have been talking about a food dish control box using collar tags. I've been prototyping this a bit lately in my CAD program. It's simple and needs one or two switches and a small DC motor. End limit switches, a timer, and a safety slip-friction drive to the cover open and closed safely
Electronics wise I'm thinking an RFID system. Sparkfun sells some all-in-one readers that look to be easy to work with. I'm considering an ID-2 with a custom antenna wound around the base of the unit. Tie this to a simple PIC doing pattern matching. If it constantly sends out, keep the dish open until clear. If it only sends on initial read, close on wrong read. A simple H bridge. I could option in a Zigbee system if I wanted to track data on a PC somewhere.