Homemade water ionizer
I actually made this for the opposite reason most people want them. I use the acidic (hydrogenated) water for my hydrogen fuel cell... But the other tank does produce alkaline (oxygenated) water... You can see in the picture how clear the alkaline w
ater is. And the other side attracts all the impurities. 
Cost me less than $20. Used an old power suply from a laptop, for power source.