Has anyone used "Seafoam?" It is an additive that comes in a red and while can. You can add it to your oil or gas - or pour it down the intake, and is is supposed for clrean out your engine.

Does anyone have an opinion on this stuff?

http://www.seafoamsales.com/

Here is a video demo on it being used
http://video.google.com/videoplay?docid=6187290865726229173&q=%22sea+foam%22&hl=en

Or it would be good for making a smokescreen
http://video.google.com/videoplay?docid=-8304205454877356623&q=%22sea+foam%22&hl=en