The Columbia Engineering School is hosting the TEDx forum at the Schapiro Center from 9 a.m. to 5 p.m. All 300 tickets for the event have already been given away, and there is a waitlist of 150. There are speakers both in person and through livestreams. This downloadable link should let you see the streaming talks, if you're interested. This is a first-time pilot event, so don't worry if you can't catch it all today.
