Using Water to Increase Gas Mileage?

I'm getting ready to install one of these gizmos in my 1997 Ford Ranger, and probably in my Ford E350 van. I bought the ebook with all the instructions and have friends who have already done this. Some of which are getting nearly 100% increase in their gas mileage. There's information all over the internet about this and it's gaining in popularity. YouTube has all kinds of videos about this. A simple search will reveal this to be true. Here are the most common sites that show you how it can be done. I bought my ebook from the first one on the list, and the rest of the sites are pretty much the same. Different ebooks with the same info laid out according to what the author thought was most important, etc.

• The Water4Gas Site
• Run Your Car on Water Site
  
• Drive With Water Fuel Site
  
• Half Water Half Gas Site
• Water Fuel Expert Site
• Water Car Pro Site

I'll post a comment on this blog when I have some results on my own vehicle(s). Also, If you have already done this to your car then I would love to see some comments on your own personal results. I know this stuff works, and if I can get even 25% increase in MPG then it's worth it to me.