That's a good one too Mac.
Your titanium shavings tale reminds me of the time my buddies and I decided to add magnesium shavings to some smokeless powder in order to see what kind of colors/flame we'd get. We'd spent the afternoon husking 12ga shells that we'd kipped from our fathers and had a nice pile of powder going. For the magnesium we'd gone after a Lawnboy lawnmower chassis with a bur grinder and had a nice pile of that going as well.
We'd built a mini mortar out of steel pipe and had it buried in the dirt a bit to hold it up and I must say that the first "test" went really well - nice high flame with great sparks and some good noise except that the magnesium made the flame burn so hot that my buddy Dan lost most of the hair on his hand lighting it off with a match. It's obvious at this juncture that we were fools so of course we decided to do it again but this time the certified nerd amongst us mentioned that he was mixing some strontium nitrate powder that he'd gotten at the local nerd supply shop into our batch as well. "Should spice things up a bit," he told us.
Well whatever the case was all I know is that as my buddy was pouring the next batch down the pipe from the coffee can full of mixture that we'd worked up (with me peering directly over his shoulder of course) the whole thing spontaneously lit off and went up in our faces. Thank God we were using smokeless powder and not black because as such we had the fraction of a second needed to jerk our heads back and only suffered the loss of all facial, forehead and arm hair as well as some scorched corneas that (again, thank God) healed up in a day or two. Damn that was bloody close! The worst of it, of course, is that our "buddies" ran all over town telling everyone about it and given the scorching sun burns we had on our faces and alien freak show hair scene as well we certainly couldn't bluff our way out of it! We were screwed and had to put up with abuse over it until we left high school and I still hear about it when I go back for reunions.
And don't even get me going on our pipe bomb phase or the gasoline/farm chemicals phase we'd gone through before that! Growing up in farm country back in the day was simply OUTSTANDING fun...if you survived.
By our senior year we'd moved on to building black powder guns from kits that our fathers would purchase for us and the rest, as they say, is history.
Cheers,
Oly