I remember waves of nausea crashing over me when I learned that the International Space Station was testing a distilling doohickey that could turn astronaut pee into drinking water, but I reasoned that if you're in outer space, you can't run to the local convenience store, so beggars can't be choosers.
Dvice has the details on an earth-bound H2O filter that lets you gargle asparagus-flavored water that only hours before was dinner and drinks. I can't understand why someone would want to attempt this short of being in geo-synchronous orbit above the earth. And out of water. And Gatorade. And Tang. Especially Tang.
H2O filter lets you turn urine into drinkable water