In chronological order:
4-6: science, specifically dinosaurs and astronomy books
6-9: obsessed with the original Battlestar Galactica
7-12: airplanes, pilots and flying
12 to late 20s: computers, video games and later Internet
14 through mid 20s: obsessed with Star Trek
18 through mid 20s: Ham Radio, electronics, amateur astronomy, physics
mid to late 20s: competitive target shooting, Highlander TV show (I wanted to live in a barge on river Senne! ) and of course swords
late 20s to 30: outdoor survival, military gear, backpacking, flight simulators, F-16 fighter (I got a realistic sim, not a game, and studied USAF flight manuals and learned all about the F-16).
something happened here and I became much much more NT-like and more sociable
early 30s: Gilmore Girls, classic novels (Tolstoy, Dickens...), eating well, taking care of my health, working out
early to mid 30s: road cycling, Tour de France
mid 30s/present: triathlons
I'm competing in an Ironman Triathlon World championship event this year! I have a crappy old computer and it is just fine, sold all my ham radios and other stuff, and I haven't even seen the last Star Trek movie nor do I have any desire to.
Wild, huh? It's pretty hard for me to accept the new me.
Oh yeah, still haven't found a woman willing to put up with me, despite me looking like a Greek God nowadays.