How could i produce fake steam/smoke effects for a steampunk costume?
I am in the process of making a steampunk/mech themed costume for an upcoming comicon. As the centerpiece for the costume i am trying to make a literal chimney tophat which i would like to emit steam or smoke or something similar in appearance from its open top. I need some kind of gadget or means to produce the desired effect that can be fixed inside the body of the hat. It needs to work in a safe manner and be compact and lightweight enough to wear inside the cylindrical part of the chimney hat just above my head.
As a back up, in case i cant find a solution to the above problem in time, im intending to hack a bubble gun and use that for a stream of bubbles but i would prefer to have a means of producing a relatively convincing stream of fake steam/smoke.
Any ideas are appreciated thanks...
P.S. im not sure if this should be posted here or perhaps in 'science' so apologies if i posted in the wrong area