I use this regularly, for everything ranging from the forgotten sudo (instead of running "sudo !!") to typos across the board.

But it does get me into interesting situations! Just the other day I was demo-ing something to my team + Director of Engg on the projector, and I ran an incorrect command, followed by "fuck" to fix it, leading to so many stares :P

Just as an FYI, you can change the prompt from fuck to something else by changing your .bashrc eg.:

    eval "$(thefuck-alias fixit)"

I'm not changing my alias though! ;)