It's probably not shocking to hear that as a teen I played Dungeons & Dragons. Rob, the super-cool guy who worked at "Games People Play" (he wore leggings, a buck knife on his belt, and occasionally carried a bo staff. We worshipped him), told me there were some good DMs at MIT's D&D club. So one weekend I wandered down Mass Ave to the appointed building and tried to find the club.
So, there was this room that was a computer lab and of course I had to check it out. The big thing I remember was that it had CRT terminals. Man, was that cool. There were a couple guys hanging out and one guy was showing off how he'd calculated the distribution curve of 3 6-sided dice and had printed them out in asterisks.
One of the things about D&D is that it provides an intimate knowledge of odds relating to the distribution curves of 4-, 6-, 8-, 12-, and 20-sided dice. Being an insufferable snot, I said he was "wrong" and that I could calculate the correct odds of the distribution faster than he could read them. Well, of course, I just had it memorized how many ways you could get 13 or whatever, but I think they mistook this as evidence that I was an MIT Freshman and they decided that I sufficiently nerdy to hang out in the lab on weekends and after school.
And that's how I learned LISP!
(And I really, really wish that I knew what that room was and who was in it in the 1981-1982 school year.)