I have multiple partners. For those in shock, look up that second word of this section. Everyone's aware and happy.
Techy/geeky topics and trivia.
Being a student.
Movies/TV: V for Vendetta, Firefly/Serenity, Star Trek, Star Wars (yes it is possible to like both!), Bones, House, Mental, Black Swan, Dexter, Perception, Dr. Who, and more.
Music: Lots of things excluding twangy country and angry rap, but including things like Great Big Sea, Bon Jovi, Flogging Molly. I've got a giant collection that I'll put on shuffle-all sometimes.
Video Games (I include these because like other forms of entertainment/art, preference in games can allude to certain traits in people): Have played a lot, but some favorites include: select final fantasies (and similar play styles like Chrono Trigger); ace combat series; assassin's creed series; guild wars (but not WoW!); and almost anything that involves two or more people that isn't a shooter.
Board/card Games: Robo Rally; Illuminati; infernal contraption; and more;
Food: Depends on mood, but give me a nicely done steak, or a great Italian place, and I'm good.
Friends who can mentally engage in a conversation.
Any physical activity more demanding than walking.
A connection to the net.
Someone to go out and have fun with.
I enjoy watching sea-changes in perceptions for their implications in the future.
I like thinking on relationships as it gives me insight into both sides and the relationship itself.
Over it all, my fascination with the past's contribution to the present and the near future's potential on the farther future describes how I think, but it isn't what I always talk about.
Or you want to - really, there's nothing wrong with being the first to message. Awkward, yes, but that's what conversation is for.