I figured I should learn about it anyway--if for no other reason than to try to keep the wits sharp. One of the big names in string theory is Leonard Susskind, and Stanford published several sets of his lectures on youtube. As I write this I'm done with lecture 6 of this 10-lecture playlist. I suspect that this is something like a survey course, since he goes into a lot of quite elementary detail--or perhaps he was reacting to his audience, since some things are shown on the fly. I hadn't appreciated the historical motivations, and there are some things I'd not seen before.
Without some introduction to special relativity and to quantum mechanics, you won't understand exactly what he's saying--but you might get some feel for the subject anyway. Be warned: the lectures are typically over 1 1/2 hours long.
UPDATE: By lecture 7 Susskind is starting to review some math the layman isn't likely to have been acquainted with.