During my web travels, I found this:
This was meant for a carbureted system; could one vacuum hose leading to the intake manifold do a similar trick?
Basically, it's trying to blow air through a distilled water+ethanol bottle, and suck the mist under vacuum into the intake manifold. The general idea is to increase mpg, and cool down the engine slightly by sucking in moist air. (I guess the ethanol is optional...)
Thanks,
Michael