If you have any interest at all in wonderfully strange and absurdly dangerous compounds, peruse this hilarious set of articles, entitled "Things I Won't Work With", by the chemist Derek Lowe
Among the lovely substances mentioned: chlorine trifluoride (hypergolic with most conventional fuels, virtually all organic compounds, and things like rock and sand); titanium tetraazide; anhydrous dichlorine heptoxide ("a liquid with a boiling point of around 80 C, and I'd like to shake the hand of whoever determined that property, assuming he has one left"); carbon diselenide (so mephitic that, when first synthesized, "the vapors [ . . . ] escaped the laboratory and forced the evacuation of a nearby village"), usw.
Among the lovely substances mentioned: chlorine trifluoride (hypergolic with most conventional fuels, virtually all organic compounds, and things like rock and sand); titanium tetraazide; anhydrous dichlorine heptoxide ("a liquid with a boiling point of around 80 C, and I'd like to shake the hand of whoever determined that property, assuming he has one left"); carbon diselenide (so mephitic that, when first synthesized, "the vapors [ . . . ] escaped the laboratory and forced the evacuation of a nearby village"), usw.