You might find toilets disgusting or fascinating. In any case, the market for really, really fancy toilets is huge in Japan.
See this article at the wikipedia on them:
One thing that seems absent (feel free to correct me) is the concept of putting a faucet and a wash basin on top of the tank and letting the greywater be used for the next flush. See this guy’s blog: [a toilet with a faucet]:http://ryanehlinger.blogharbor.com/blog/NewApartmentTokuanOsakaJapan/_archives/2004/12/29/218595.html
One thing interesting is that the toilet seat (not just the lid) has a cover so your butt doesn’t have to touch cold plastic/wood/etc.
This site [(little things Japanese)]:http://www.jun-gifts.com/others/littlethingsjapanese2/littlethingsjapanese2.htm has lots of pictures, even if it’s not as well written as the wikipedia entry.
Anyway. Enjoy! I’d write more on this wildly fascinating topic (no, really, it is), but I gotta go eat now.