Ethos gasoline additive - fact or fiction?

 A colleague (not a Prius owner, but interested in alternative fuel vehicles)
asked me if I knew anything about the claims being made by a company that
sells an additive called Ethos (I think it's basically acetone).  The claim
is that mileage can be improved by up to 20% or so simply by adding 1 oz.
per gallon of the stuff.  Read about it here: http://www.savegastoday.net/ .
My brief bit of research suggests that acetone may have some positive effect
on gas efficiency, but my gut tells me otherwise, especially considering the
hard sell.  I have no interest in it for myself (a Prius owner), but I told
him I would ask the Prius community, since they tend to be well-informed in
these matters.  Any opinions or facts to share?

Thanks,
Doug

 

Aha, the MLM marketoid fraud.

Acetone does real good on plastic.  Just put it in yer tank and prepare to
pay for the replacement parts eaten up by the chemical dissolving them.
Also seems like the stuff would redeposit plastic inside that gas engine's
cylinders so tack in an engine re-build too.