I knew this kid in high school who had a yellow rain coat(the ones you get for like 5$). He taped the hood to a welding mask so the coat was air tight. Than he used an electric air matress pump that he modified to suck in air from a bong. The pump blew the air into the coat. The coat would blow up like a ballon with smoke. One good 5min walk in the coat would destroy you.

Besides that we used the pump to fill up trash bags that we would throw over someones head while they wern't looking and tie it off.