Go here:

http://www.ftc.gov/bcp/conline/pubs/autos/gasave.htm

and read.  This falls in the "Fuel Line Devices (magnets)" category.
---------------------------------------------------------------
Tom Young                       '81 Vanagon
Lafayette, CA 94549         '82 Westfalia
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----- Original Message -----
From: "Stephen Overmyer" <s.overmyer@UWS.EDU.AU>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Tuesday, September 23, 2003 11:36 PM
Subject: The latest in snake oil....

>    Hi Guys,
>
>    I was recently sent this piece of spam,but I couldn't resist
>    having a look.
> >http://www.ftmm.org/default.asp?axel=8577
>
>    It's for one of those fantastic-too-good-to-be-true
>    fuel savers and performance boosters.
>
>    Interesting how  in the FAQ section,the only question not asked
>    is "how the **** does it actually work?"
>    Just lotsa crap about superconductors and fantastic claims
>    about how amazing it is....and a bargain @ $89.95
>
>    Has anybody actually tried something like this (and is prepared
>    to admit it)?
>
>    I'm curious if it's only as useless as an ashtray on a motorbike
>    or indeed as useless as tits on a bull...;)