No better icebreaker exists than taking off your pants in a crowd. People who normally would never speak to each other on an MBTA train had plenty to talk about once they "depantsed" on Saturday afternoon for Boston's first annual No Pants 2K8. At first, when aspiring pants-free T riders gathered at Alewife station, the event was at risk of being a bust. The area between the gates and the stairs was packed with people,......