well i've this ideea after watching some clips on google video. all you need is to drop some mentos into a 2 liter bottle of diet pepsi or coke and step aside very fast.
The thing is my hand is a funell made out of a pice of paper which i used to drop the mentos into the bottle.
PS. Please diregard the dumbass look on my face, its just one of those pics.

PPS. Use only 2L bottles, the 1L just have too little of an effect.
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