Originally Posted by
notquiteaff
Does the water to make hot fresh poo, eh, coffee, come out of the same tank as the hand washing water?
Yes. That is why you hope the water was boiled properly. Even then the "sterile" grime can be disgusting and not good for the digestive tract.
I use the paper cups in the bathroom, often in conjunction with bottled water and/or as part of ways to more compltely clean my hands. If there aren't paper cups in there, I may consider taking in a disposable cup from the economy class meal service or from the galley.