I've used this feeder for about 5 years now and I like it a lot:
http://www.amazon.com/Petself-Elect...rder/dp/B003T7UH22/?tag=felinediabetesfdmb-20.
What I did with my two cats (because one is a gobbler and the other was not and I was worried he would eat all the food and leave her with none), was I started feeding them every meal at opposite ends of the kitchen. Each of them only were fed in their "spot". I bought two feeders. When I needed feed them during day when I was gone, I set both feeders to go off at the exact same time, and put one feeder in each spot. I fed them 4- 6 times a day (with and without the feeder), so their portions were small enough where my non-gobbler would finish most of her food before the gobbler would finish his and run to clean up the rest of hers.
I was able to do this by experimenting by setting the feeders and observing their behavior when I was home. If you can get them on a regular feeding schedule and routine (e.g. feeding each cat in a different spot for every meal, at the same time, every day), that helps a lot.
I usually fed them 4 times a day, so that meant I would shoot and feed at 7am when I left for work, set the feeders for 1pm (6 hours later), feed and shoot at 7pm, and then feed again at 1am since I was getting up to get Bandit's daily nadir blood test at that time anyway (I would set an alarm and then go right back to sleep).
I had to do things this way because Bandit would eat and eat until he puked if I tried to free feed canned food by adding water and leaving it out, or he would sit and gnaw on the frozen food nuggets if I left those out, and he would eat the other cat's portion because she wouldn't touch it until it was unthawed. I also wanted to make sure he was getting food at +6 during the day while I was at work, because that was when his blood sugar usually dipped the lowest and I wanted to make sure he had food available for a boost at that time.