(1) When I was around four years old, the kid across the street, Stevie Radle, and I decided it would be a good idea to lock ourselves out of my parents' house while they were out for a walk. I don't know why, but we thought this was a pretty fun game, at least until they came back. They hadn't brought any keys with them.
(2) During high school, I was an intern at the local university's planetarium. We put on shows, took visitors up to the observatory, and went down to the Connecticut shoreline at odd hours to view Halley's Comet. As a result, I got seriously interested in astronomy and, for a while, thought of majoring in it in college. Alas, I didn't care for the hard-core physics stuff, so that went by the wayside. I did, however, get to know constellations and their stories extremely well. I even pasted glow-in-the-dark stars in constellation patterns all over my bedroom ceiling. When the lights went out, the winter night sky - Orion, Taurus, Canis Major - came into view. Houseguests (like my grandmother) who slept in my bedroom after I moved out were kind of spooked by this.
(3) I have a weird photographic memory for books, titles, and cover art. Normally I only need to see a title/author combination once, even if it's just on a shelf at Borders, to have it register and stick. This information usually has no practical purpose, but it comes in handy for trivia contests or when people play the "I know it's by so-and-so and has a blue cover" game. It's also useful when I need to find a book on my shelves at home. Unfortunately, this ability doesn't extend to remembering people's names or faces. By the time a student's left the reference desk, even if I've been helping them for 15 minutes, I've already forgotten what they look like unless it's someone I've worked with a lot.
(4) I made some extra money one holiday season by working at a mall music store. They had a really bad selection of jazz, blues, and folk music, among other things. Not a surprise. I was a big folk music fan, and sometimes got into conversations with customers about our favorite groups. I'd even happily refer them to a store with a much wider choice of CDs if they had trouble finding what they wanted at the mall and didn't want to wait for a special order. A couple people asked me if my boss knew I was making referrals to their competitors. "Of course," I said, untruthfully. I didn't realize what a stroke of business genius this was, not having seen how it worked for Mr. Macy in Miracle on 34th Street yet.
(5) My first ever official publication was a humor piece called "Are You an Internet Nerd?", which got accepted to the Usenet group rec.humor.funny back in 1991, when I was in linguistics grad school. There are still copies floating around the web. I was real excited when the Electronic Frontier Foundation asked if they could reprint it in their online newsletter. Some of the references still make sense, amazingly.