Good ol' "Serendipity"
It was on this day in 1754 that the word "serendipity" was first coined. It's defined by Merriam-Webster as "the faculty or phenomenon of finding valuable or agreeable things not sought for." It was recently listed by a U.K. translation company as one of the English language's 10 most difficult words to translate. Other words to make their list include plenipotentiary, gobbledegook, poppycock, whimsy, spam, and kitsch.
The invention of many wonderful things have been attributed to "serendipity," including Kellogg's Corn Flakes, Charles Goodyear's vulcanization of rubber, penicillin, inkjet printers, Silly Putty, the Slinky, and chocolate chip cookies.