Pix0r

Hi All, First off, please forgive me if I posted this in the wrong place I need some help. I'm busy working on a project where I need a certain liquid, since I'm not a chemist but rather a graphic designer I tend to struggle. So I was hoping some bright spark here could help me out. What I need is an absolutely non toxic liquid (when I say non toxic, I mean you should be able to drink gallons of the stuff with no dire effects. This chemical needs to have certain qualities: 1.) As mentioned, 100% non toxic. 2.) This is the big one. It should react to air, what I'm after is that when exposed it turns into a coloured smoke. 3.) Odorless would be good, unless the oder could be pre-defined (i.e: it would smell good.) 4.) The ingredients should be easily accessible. * 5.) The ingredients must be cheap. 6.) Less should equal more. The more smoke I get from the least amount of liquid the better. I'm looking at not more than 50ml to 'cause a decent amount of smoke. *=Not such a problem. I understand that this could be a bit hard to understand so I'm going to try and draw a mental image to clear things up. Say now you have a standard coke bottle containing coke and (for argument sake) 30ml of this liquid. When the bottle is opened, the liquid contained inside reacts with the air which 'causes the liquid to evaporate into a coloured smoke. I hope that brought a bit of light onto the subject. Does anyone have any ideas formula wise, or know who I could talk to ? Thanks for any help, Pix