Urine to Water, step up and have a drink. http://news.yahoo.com/s/usatoday/20080515/tc_usatoday/ontapinspaceurinewillnotgotowaste
The article doesnt mention it but the russian astronauts did use the system during an emergency in their space station. There is another way although still far out in the future . Spaceships can draw water from comets on their way to far reaching systems or at least some of the more adventurous scientific minds think its possible.
