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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.
Never heard of those, but if they are on par with project Orion I have some nice readings to do today.
If you're into hard sci-fi and you're looking for a good read, they actually dropped a pretty good recommendation with that reference at the end - Larry Niven does a great job of blending real-world theories like Dyson spheres and advanced propulsion drives, with some of the more far-flung standards of the genre like an intra-planetary teleportation grid.