This is not a viable idea due to the primary factor that fireworks do not have enough propulsion to launch a human body and the secondary factor that fireworks are explosive and dangerous
Shada,
Fri 21 May 2010, 0:55,
archived)
I'm sure enough fireworks would provide enough propulsion.
Mu Dinofiddler,
Fri 21 May 2010, 1:00,
archived)
Mythbusters did something on thisI think it just went all over the place and exploded on the floor about a meter away
Edit: mythbustersresults.com/episode24
(Edit: mythbustersresults.com/episode24
Gawain the oven safe flan tin willy bum fart poo,
Fri 21 May 2010, 1:02,
archived)