Magic smoke (properly called "Mystic Smoke from fingertips") is also a product sold at many
costume and
magic supply stores for
street performers.
It's not effective on stage, but up close and personal, it makes an impression. It's a resin-based paste that one rubs on their thumb and middle finger ahead of time until it's warmed up and spread around. Then, when a dramatic effect is needed, you rub or snap your fingers and if done right, superfine strands of the resin "magically" float off, off and away.
It looks like you created smoke, wisp, or perhaps spiderweb off your fingertips, and honestly it looks pretty darn neat. It's roughly flesh-colored (a yellow-pink-clear) so no one sees it on your fingers ahead of time. Your skin keeps it warm, so you can produce "smoke" any time until you run out or wash your hands.
However, the observer with the accute sense of smell can tell something's fishy because it has a very distinctive sap-plastic-chemical smell that your skin shouldn't make.
Fascinates small children and their parents; mystifies cats.