In 2005, I was a freshman in college. Obviously, I had friends that could get me alcohol. But, we were broke college students, so we always got the crappiest vodka possible.
Now this is when genius theater kids that wanted better vodka came in. What did we use to make it better?
A water purifier. Boom.
We filtered it probably like, 4 times and we thought it taste better. (We were also pretty buzzed.)
Moral of the story? Be resourceful.
Oh, and don't do this near a computer. I shorted out my right side of the keyboard because of this.
Disclaimer: I am not condoning underage drinking by any means!!