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xkcd #2929: Good and Bad Ideas
(imgs.xkcd.com)
Alt text:
While it seemed like a fun prank at the time, I realize my prank fire extinguishers full of leaded gasoline were a mistake.
I like Footfall, but it's also a little over the top for me.
Co-written by the guy who tried to sell the US military the concept of "rods from god" (orbital kinetic weapon). I wouldn't expect anything less.