Fracking. As in the f-word substitute used extensively in Battlestar Galactica. Somehow, I’ve come to know a lot of people who use it in real life.
Then again, it made my interpretation of all the "No Fracking" signs found in every other yard in my area of NY really interesting for a while back before the environmental issue became a household term.
(Side note, scrabble as a euphemism has completely overtaken my brain’s first response to that term, so now I have to inwardly snicker every time someone mentions the game—even offline—before remembering that there’s a non-euphemistic definition of the word.)