i would try to scrouge up enough to take public transportation as far as possible in whatever direction you'r going.......i've never hitched out of there before....but yeah.....where you tryin to get to ?
the chinatown bus seems to be the main way kids get in and out of b-more/richmond/DC/philly/NYC.....
I haven't hitched out of B-more, but I have hitched out of Maryland and Northern Va, and it takes at least a few hours just to get the first ride out. Once you're out of the area it isn't so bad, but I'd get a bus out if I could.