When I was 14, I was an idiot. You know, kids with gas and leaves... bad day. Burned my legs and hands real bad, 1 month in the hospital and 2 months out-patient.
Second time, i was 16 and my chemistry teacher did it. A hot-air balloon experiment gone awry. We had a trough in the dirt outside with a steel can over it. He dumped raw alchohol on the trough and lit it up. All was well until the fire went out. Or he thought it went out. He was dumping it from a gallon jug. Since he thought the fire was out, he dumped more in the trough, i was standing about 5 feet directly in front of him. The fire wasn't out, it went into the bottle and blew lit alchohol out all over my legs and filled one of my shoes. That was another bad day. 2 months hospital, 1 month out-patient.
Now I'm 27 and playing with nitro-methane... aparently still not to bright.