Here is a pretty funny anti-smoking commercial. There are a bunch of people outside on a balcony smoking. A guy walks up and he is about to go outside and light up when the balcony collapses because some many people are out on it. The guy gets scared and runs off. Apparently you are somehow suppost to link this with smoking kills you. In any event the way I see it is the balcony is really a scissor lift and the city background is just a greenscreen or painting or some such. They just punch the scissor lift, shoot of the smoke, and have the people scream to make it look like the balcony falls off.