McAfee SiteAdvisor gives a Yellow Alert for the site you linked to, Walt.
Apparently, someone reported getting 30 e-mails a week after giving that site their e-mail address.
Additional note, I had a similar problem with a local NBC affiliated station several years ago. The site had gone to a membership format and then blocked content on their website if you did not sign up, so, like an idiot, I signed up. Sure, I got to see the news posted on their site... and then an inbox full of all their blasted SPAM too.
After complaining about all the unwanted clutter in my inbox the problem did go away for me though.
As for the 110 gas mileage story I think you were linking to, that would be cool if it worked. I would like to see the MythBusters prove it before I believe it though.
The MythBusters did a show on several gas saving gadgets and schemes a while back and showed how these gadgets and schemes were all impractical (and dangerous), mistaken, or outright fraudulent claims. None of them worked as advertised, and most actually caused you to get even worse gas mileage, if they showed any results at all.
So, I remain the skeptic, as ever, until I see independently verified test results.