A massive explosion, bro. That's what you get. If you want to fast forward to the good parts, I'd suggest starting somewhere around 3:45. Though to be honest, hearing Professor Roy Lowry of Plymouth talk about the explosive potential of liquid nitrogen in its gaseous state is pretty damn interesting. [YouTube via Neatorama]
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Maybe not quite to the same effect but pretty close, you could use the aluminum + draino (or toilet bowl cleaner or something) in a plastic bottle.