You can’t go past the Google team for an intelligent and engaging audience. I spoke there 2 years ago to an audience of about 100, and a similar sized group turned up yesterday. There were some quite challenging questions on my views about the current state of the world economy, so the talk went well over the allotted hour
Below is the video of the talk; the sound quality is a bit poor (I recommend using earphones to listen to it), but there is also an audio recording below that may be easier to understand. If there are enough complaints(!), we’ll blend the separately recorded audio with the video.