All automobiles are installed with units which add color to vehicles' exhaust at various levels of emissions: low-emission vehicles are uncolored, midlevel-emission vehicles light pink, and high-emission vehicles thick neon pink. Scents of varying pleasantness and offensiveness can also be used for additional impact. Drivers will become enraged at SUVs and Hummers for smoking up the streets; new environmental concern is aroused.-- oatcake, May 21 2003 wholly smoke! security system http://www.acuraemb...com/whollysmoke.htmnon-toxic, dissipating smoke. [oatcake, Oct 05 2004] corvus oil (or Canopus).-- bristolz, May 21 2003 Can't you colour your exhaust just for the fun of it, rather than as a means of identifying pollution emission?-- monkeyseemonkeydo, May 21 2003 Sure. Though, I got the idea from seeing a truck belching ugly black smoke, and thinking how absolutely repulsive it was to actually see the pollution, so this was the first thing that came to mind.-- oatcake, May 21 2003 Right... because Bob knows the colorant wouldn;t be a pollutant.-- belg4mit, May 22 2003 "...obscuring smoke is 100% non-toxic and safe for humans" [link]-- oatcake, May 22 2003 Not exacly the same thing, but I seem to remember an idea by one city's bus company to add strawberry scent to their diesel. Can't remeber where I saw it though...-- cevilthedevil, May 22 2003 The temptation to weave in and out of other traffic (like a formation flying team) would be too much...-- hippo, May 22 2003 oatcake - that uh, non-toxic smoke has never seen the tail end of um, a tailpipe has it?-- thumbwax, May 22 2003 No, but it was addressing the colorant-as-pollutant issue belg4mit brought up. And now that I think about it, scented exhaust could be a bit hazardous...if the kids like glue and permanent markers, surely this would be a more pleasant choice.-- oatcake, May 22 2003 If kids ingest it, does it make their tailpipes emit colo(u)rs too?-- saker, May 22 2003 I saw a product in an 4x4 magazine that could be added to your tank to give your exhaust a scent. Strawberry, pina colata, cherry, watermelon...-- sjruckle, Jul 08 2004 Anyone see the movie " Up In Smoke " ? Talk about scented exhaust !!!! But then again,who cares, ? The half baked have already digressed into wondering if the exhaust colorants would be healthy for you to consume , nevermind the exhaust itself.-- kingwuz, Nov 13 2006 random, halfbakery