Movie *feces* aside, my closest call is a weird one.
It was ~1980, and I was a nerd in high school. So nerdy, in fact, that I also was in a historical reenactment group based out of the Fort Pitt Museum in Pittsburgh PA (right at the tip of the triangle!). The Royal American Regiment, 60th of Foot. Uniforms (tailor-made!), tricorner hats, weapons, groupies -- we had it all, man.
Anyway, I was a corporal in the artillery, meaning I led a group on our cannon ("Bertha", of course -- we're nerds, but we're unoriginal). We were doing some exhibition at Point State Park (see picture, below; the weird square thing is the outline of the old Fort Duquesne; the weird pointy thing at the top of the trees on the right side is one corner of Fort Pitt, now housing the museum) and my cannon was to the starting gun for the boat races of the "Gotta Regatta" that the city held every summer. We were stationed at the very tip of The Point for that purpose.
The cannon and its carriage together are large and heavy, even more so than PaunchyBald. It had a 3" bore and was pretty potent when fired (again, oddly like PB) -- despite two guys standing on its tail, it still came back about a foot from the explosion when fired. Four guys make up the crew working the cannon: one to clean the bore ("worm"), one to sop the bore ("sponge") to quench embers that might ignite the black powder subsequently fed down said bore, one to load it, a powder monkey to assist the loader, and one to fire. I was that last guy. The "worm" and "sponge" stand forward of the wheels, one on either side. At least, they're supposed to.
We finished our exhibition portion, and then we loaded the cannon. There was a good-sized powder charge (2) inside, tamped down nicely, the "touch hole" (3) (oh, you guys are going to have a field day with these phrases!) was filled with powder, and there was a nice mound of black powder on top of the cannon. That's the part I lit to fire the thing. We were just hanging out, waiting for the signal to fire it to start the main race.
I noticed some stray black powder on one of the carriage rails. So I absent-mindedly touched it with the slow-burning I use to fire the cannon, intending to flash it off. Well, I hadn't noticed the stray powder was ALL OVER the carriage and the storage boxes flanking the cannon. Big flash, hiss, and smoke as basically everything surrounding the cannon ignited, burned briefly, and went out. Flame came extremely close to the powder mound over the touch hole, which would of course have fired the cannon.
I looked up, and my friend Bill Vallinson ("sponge" that day) was standing
directly in front of the muzzle (where he does
not belong). He was as pale as a ghost, as he thought the cannon was going to fire. It would have either blown a hole where his chest was, or it would have blown him into two pieces, and tossed him into the Ohio River. He told me later that I turned just as white when I looked up and saw him.
(I had you at "nerd", right?)