Toilet train them, though do not teach them to flush. My cat Pyewackett was toilet trained. I really miss him -( It was refreshing to not have to deal with kitty trays.
I realize this was only reopened for spam, but since it’s reopened… I had started a similar thread around the same time, but with a slightly different take. Net result of thread: no, don’t flush cat litter. It can clog up your sewer line or septic system, and
Please don’t try corn if you have a full-grown male cat. Learn from our mistake. It intensifies the urine smell and it turned even my stomach and I don’t puke easily.
There is some evidence this kills sea otters.
?? If by full-grown you mean intact, of course you will have a smell issue, regardless of the type of litter.
I have three boys and a girl, all neutered, and don’t have a problem. I use World’s Best, which is corn but formulated to be as heavy as regular clumping silica. I don’t like the other corn litters because they’re light and track and dust everything nearby, but the stuff I use is great.
And to go along with the theme started by the OP, I landfill the cat poo/pee/litter, but I feel better about it by using biodegradable poop bags along with the corn litter.
No, I don’t mean intact, I mean adult.
Thank you kindly.
It’s been flushed.
How much space do you have, and is it near a water source and a drain? In that case how about acat genie?
I have been wanting one, but we really do not have a good spot for one in our tiny house right now - we would have to move the stacked laundry out to the barn and use that spot instead … but if frex you had a normal laundry closet that was designed for side by side full sized units, you could just get the stacked type and out it down where it could share the water and drain lines. When we finally move, we are going to make sure that we have space for one.
Wow, what a strange place the world is, where a thread about cat litter from four years ago makes me a bit nostalgic.
In any case, I don’t have this problem any more 
Moved to another country and left my cats with friends. I miss them so much.
If I did still have them I wouldn’t use a machine to clean their litter. I did try that before, but after a few months when the cleaner bar would fling nasty bits all over the bathroom like a kitty poo trebuchet, I stopped using it.
Man. I do miss my cats.
I tried stuff that claimed to be flushable, and it clogged up the toilet.
This was over ten years ago, however, so maybe they’ve made cat litter that really is flushable now.