I just got off a plane, and, as you know, a full plane is a breeding ground chit-chat among complete strangers. I hate small talk to a degree that many would say is excessive. My strategy is simple: endure the chit-chat until the inevitable question arises, "So, what do you do?" My trusty answer, "I'm a logician," typically elicits nothing more than an "Oh," and then stops conversation cold.
The last few times I've used this tactic, though, it backfired: my interlocutor said something like, "How interesting. Could you explain what that involves?" Yuk. Today, though, it worked like a charm. After I claimed to be a logician, the woman next to me picked up Sky Mall, and "shopped" for the duration of the flight.