you can use a 5gal airbottle similar to what we use at the track to make your pnuematic mobile. no flame involved. and since its air powered, you can launch things that you cant launch with hairspray. we've shot water, rotten cottage cheese etc...and trust me, its as powerful as hairspray, but the nice thing is that you can vary the pressure. so if you want to say, launch eggs, you can do it with out exploding them before they leave the barrel, with some experimentation.
ok, enough
j