Since I'm lazy, I own a Litter-Robot (expensive self-cleaning litter box). It's actually a pretty nice unit (seems much better than the competition, although I haven't owned any other automatic). The basic mechanism is very similar to the roll-over boxes you can buy at Meijer. The key difference being that it rolls itself shortly after the cats have used it.
Anyway, after working well for a while, mine stopped automatically rolling itself. For a few days I could still hit the 'cycle' button on the front, and I ignored the problem, but eventually it stopped working entirely.
I sent an email to the company, and got a response back without too much delay. The response included some troubleshooting tips, and I was able to find the problem (there's a wire in the 'cat is in the box' sensor that broke off where it's connected with a crimp connection). I temporarily fixed it with some solder and sent a note back to the rep. The company is sending me a 'better' fix for the issue.
All in all, they did a really good job.
Good product + good service = happy customer.
I highly recommend this product to anyone who has cats and is mildly lazy (or who wants to have better litter utilization or who wants to control odor better) like me.
You still need to check the box every day (or 2) and empty the waste drawer, but it takes about 10 seconds to pull the bag out and put a new one in (and you can use regular trash bags, or plastic grocery bags if you stretch them a little).
