We got three kittens a few weeks ago who can fill up a litterbox faster than you can say "cheese!"
Anyway, we just had to do something about cleaning out that horrible thing so I thought of spending $$$ to buy one of those automated ones but then you've still got to invest in filters and liners all the time.
Instead we found the coolest thing ever that's so easy to clean out (without touching anything) that we don't mind doing it 2-3 times a day. It's called a Roll'n Clean by Omega. You just roll the curved lidded box upside down and back again and everything is collected in a pull-out drawer. Paid around $35 for it at Petco. WELL WORTH IT!!!
Here's the link:
Roll'n Clean Large Litter Box