"Fireman Fridge" You guys should get one of the really powerfull hoses that the fire department uses and when someone goes to open a fridge (that they don't know is rigged with a hole cut in the back of it), someone should turn the hose on and mow down the person/people outside of the fridge with the hose, it would be totally unexpected. You can even hallow out the inside of a fridge and have one of the cast members stand inside of it with a firefighter suit on and spray the victim down.
"Johnny the fireman" If someone is smoking a cigarette or anything else on set you should have a cast member, prefferably Johnny run inside a house or on set either by himself or with an entire crew of Firemen and have them all run towards the victim who's smoking at the same time spraying multipul fire extinguishers or a couple of the high pressure water hoses that they use and bombard the smoker.
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