In a past life, we would fill trash bags with a mix of oxy-acetylene and shoot them. Just about anything larger than a 22 would set them off, they were so unstable. One night a friend was filling one by hand and we surmised his poly shirt generated a static spark to the bag and boom. It blew off his shirt, burned all the hair off his chest, eyebrows and arms and knocked him on his arse. He was pretty much unharmed except for his hearing.
Another venture with the same crowd and same era, we inflated a weather baloon (remotely) with couple hundred yds of hose, and detonated it on a dry lake with a surplus piezoelectric bomb trigger and a broken flash bulb. That one rocked to desert floor and had a visible shockwave.
Then there was the 3000 psi water rocket...
Definitely an era of stupid antics
