I use Swheat Scoop its made of wheat, does clump, but is not dusty like clay and does really well at odor control. Most importantly the cats like it. I also provide them with a big box - not a litter box at all, but one of those under the bed boxes. (I have a basement fortunately, so I have space to do this)

My cats are entirely indoors. Outdoor cats around here disappear way too regularly. I would be absolutely heart broken if either of them was eaten by a coyote, killed by a raccoon or run over by a car - these things all happen here even though I live in the middle of the city!