If you're on a budget, look at one of these:
http://omegapaw.com/Rollaway.html
The rollaway litter box isn't automated, but it does look like it makes it really easy... it does put the nasty stuff in a pull-out container, and it's hella cheaper than a littermaid. Like 30 bux.
I don't have one, I've just been thinking about trying one.