Ever use the toilet on a Mexican first-class bus?
You have to buy toilet paper at the station and I don't even want to think what a third class Mexican bus is like.
I took a 16-hour ride on one once. The "entertainment" was when the drug officers came onboard with their German shepards and checked everyone and their luggage.
BTW, if a Mexican officer asks you if you have any drugs, never ever say "Sure, whadya need?!" (just kidding on that one - ain't quite that dumb).
Okay, so to aim this towards space, I've heard the Space Shuttle toilets leave something to be desired in terms of convenience. How is the ISS toilet in comparison? In either case it must beat the diapers with tubes they used to have to use.