Snowballs rule! Not only are you clean, you are refreshed! I just use a square or two of TP for the final polish.

I am also in the boiling water only cooking fraternity. Never any food in the pot, so nothing to clean. The plastic bowl get rinsed out, and I drink the water for that extra edge of hydration. I always let the bowl dry thoroughly, and expose it to the sun. Those little bacteria don't like that high-altitude sun. Of course, if you're snow camping, you can always clean the pot with ..... a snowball!