[As ever you can read this on the BBC News website]
On Monday I went to see Clay Shirky talk at a lunchtime seminar hosted by the Demos think tank, travelling in to London earlier than I needed to on a crowded train, sitting on a slow bus across town and then squeezing into a bright but too warm room to sit on a hard seat in order to listen to something which was being recorded and will later be available as a podcast.
Clay was charming and intelligent and funny, and I got to hear him thinking out loud about the impact of social tools on international politics, which was fun, but I could have done all that by listening in online, or even by watching the stream of brief reports appearing on Twitter, the communications service that is currently taking the net by storm.
Instead I sat there offering my own online commentary on what he was saying while looking up references on the web as he talked.