: Stare for a few minutes at his picture (if on RJ, preferably when logged out so I don't show up on his Who Viewed Me list LOL). Wonder at what kind of person he would be (usually, I convince myself well enough that he's probably an egomaniacal piece of shit) then sigh heavily and close the pic.
No I don't jerk off to his pic. LOL. That is I don't imagine the sex, I'm more likely to imagine idiotic romantic things we could be doing together. Walking on the beach hand-in-hand, baking cookies, snuggling with him on a rainy day, arguing on the merits of Star Wars over Star Trek, torturing kittens, burning churches, committing bank robberies...
Almost always, I never do end up talking to him.
I know, I'm pathetic. Real Life
: Get two or three covert looks at him before ignoring him almost completely, just short of being outright rude. I just act as if he barely existed. ROFL.
Unlike online, where I can happily ignore how attractive someone is and talk with him normally, in real life the moment I start getting attracted to someone is the moment the relationship will never be more than a distant friendship/acquaintance. Especially when there is no indication at all that he even notices me then I turn the force fields on.
Same thing though, usually romantic things bordering on the sickeningly sweet. It's still a sort of physical attraction but with psychological factors as well, as I also notice his sense of humor, the way he laughs, the way he treats other people etc. (and if he turns out to be a certified asshole, those feelings putter out very quickly indeed no matter how hot he is).
Very rarely does someone immediately make me think of sex and those are usually the people who just exude that kind of thing. Something about the way they act, look, and smell thing. And those rarely get past the physical attraction and turn into crushes anyway.