The Slingshot. Purifies via vapor distillation. Last I heard Dean Kamen made an agreement with Coke where they would help Coke build a water soda fountain in return for Cokes distribution network. Not sure what has happened since.

Hope it still works out, but I feel another sad Segway story coming up.

https://en.wikipedia.org/wiki/Slingshot_(water_vapor_distill...