Gimmick or great idea?

I ran across something rather by accident earlier today: Drive Water.

Nope, not dive, I said drive.

Supposedly it is the idea of adding a tank under the hood of your car so that you can partially run your vehicle off of a mixture of distilled water and baking soda.
Here is what the website I came across says:

"You don't change your engine or computer. A quart-size (95O cc) container is placed somewhere under the hood. You fill it with DISTILLED WATER and a little bit of BAKING SODA. The device gets vacuum and electricity (12 Volts) from the engine, and produces HHO gas (Hydrogen+Oxygen)."

Sounds like a gimmick to you right? I thought so too. But, what if it really works? What if we can solve the issue of having so much poison pumped out of our exhaust pipes by adding a simple device under the hood?

Check it out for yourself. http://www.drivewatergogreen.com/