This is an ongoing joke between me and Dan, but it never fails. If you see a dude wearing girl jeans anywhere near Boston, ask him if he's from Allston. Nine times out of ten, he'll do a double take and say "yeah, how'd you know?" The other time out of ten, he'll say "Brighton."

It came up on yelp, apparently.
http://www.yelp.com/topic/allston-guys-wearing-girls-pants