Ive always wanted to try that. Maybe the next cat.
I do have one of the petsafe automated litter boxes and it does a pretty good job. Plus I only have to deal with it like once a month.
Yah, that was the first thing I did was train him. And good thing too, my wife is allergic to cats, but can tolerate him because the house doesn't smell like litter, and he isn't allowed in our bedroom so he isn't getting cat-hair all over the bed. A couple tips, it works better if you have access to multiple toilets. If mine doesn't see it flushed after he pees when he only has access to one, he will sometimes poop on the floor beside the toilet. And don't teach them to flush on their own, or your water bill could get high fairly quickly, as they figure out it is a good source of "fresh" water.
I've also trained him to high-five, shake, pray, and roll over because I am slightly insane and like the torture... And teaching him to sit and stay is great when people are coming over so he doesn't escape the house. All in German, because it is satisfying to yell at him in German instead of English...