I'm a huge fan of people using the wrong word to express the wrong thought. Part of it is the deliciousness of being a grammar/vocabulary Nazi and secretly judging the person guilty of the misuse, but mostly it's the unintentional humor it creates. It's sort of a guerrilla chuckle. First you're in a business meeting expecting all sorts of boring nonsense bandied about by people acting important and then your boss throws out something like, "In the coming physical year we can expect to get more bodies." It's not that funny, granted, but hearing the boss confuse fiscal and physical is a petty little reminder that maybe, just MAYBE, you're more qualified to do his job...and therefore better...and therefore justified in playing Brickbreaker on your Blackberry when you probably should be nodding attentively. Whatever. As a side note: In case the boss in question is somehow reading this, I really don't believe I was more qualified to do your job. The preceding was for humor value...which I suppose was just ruined by way of my explanation.
A buddy of mine who's wife teaches at a well respected Southern university called me today and read the opening sentence of a paragraph from one of her student's papers regarding Title IX legislation. The student in question, dissecting the complexity of his point, decided to put it in "lame man's terms." Awesome.
My personal favorite incident of word misusage occurred recently in a moment of intimacy between two friends who will remain unnamed. The couple in question is limited somewhat in the realm of sexual positions because the female has a suspected retroverted uterus. I personally had never heard of this condition, but apparently it occurs in something like 1 in 5 women. Check Wikipedia if you're curious...or writing a term paper. Anyhow, the condition means that the uterus is tilted slightly to the back as opposed to the front and can cause pain in certain sexual positions. The couple in question was in flagrante delicto when the female, intending to make a joke about her suspected retroverted uterus, instead referenced her introverted uterus.
My vagina likes to spend time alone and is uncomfortable in social situations. Classic.