in my experienceI went to the Emerging Tech conference back in 2003 and had an eye opening week. I didn't know it at the time, but there were important people there (well, important to me as it pertains to my job type). I met Clay Shirky in an elevator and contributed to a back channel doc (we used SubEthaEdit I think) during a talk led by Stewart Butterfield. The resulting doc is still out there on the internet and is still interesting.