I've found the patterns of social behavior throughout the conference to be very interesting. Particularly during the poster sessions and free periods when we as participants shape the format of the meeting. The nonverbal communication of poster presenters is particularly interesting. The way a presenter stands, gestures, and the amount of eye contact they give to the "passers-by" has and intriguing effect on the number of people who stop and discuss the poster with them. And we as "passers-by" are clearly making judgements about the presenters on this non-verbal communication and this is how we chose to engage. Such choices can have an important affect on the professional future of both the presenter and their audience, so it is interesting that non-verbal behavior will have such significance.
Sorry for the rambling-thought post, just a bit of mental regurgitation during a lull in the conference.