Started out with XO Laptop Hacks. I just got my OLPC XO not that long ago and I haven't had time to do much with it so it was interesting to hear more.
Next I went to the presentation on CouchDB. It's an interesting project - written in Erlang, primary interface JSON via HTTP, started by one guy on his own, but now IBM pays his salary.
I couldn't miss Jeff Jonas's talk on behind the scenes in Las Vegas - he's an entertaining presenter. His talk didn't have as much software content as last year, but it was still good.
Synthetic Neurobiology was largely on the theme of "body hacking". One of their more clever hacks was to introduce genes into neurons (via a virus) that make the cell sensitive to light. You can then trigger the neurons to fire (or suppress them from firing) using light. Wow.
The day (and the conference) ended with more keynotes. First by Alex Steffen of WorldChanging (who I was disappointed to see carrying a disposable plastic bottle of water!) Then a presentation on Twine - yet another social network app, but at least with some interesting semantic web aspects. A brief talk on Digital Democracy about the use of the web (and social networks, of course!) in politics.
And the final talk was by Timothy Ferriss of the (4-Hour Workweek). I'd seen Tim around during the conference, attending talks. My first impression was that he was short. A bit like seeing an famous actor and finding out how short they are. He also blended in pretty well carrying his backpack around, although without the ever present laptop of most people. But when he gave his talk he definitely had a bigger presence and charisma. Unlike every other speaker, he did not have any powerpoint slides - he just talked. If you've read his book and blog it was nothing new. Despite being a wing nut in many ways, I still find him "inspiring" if that's the right word. The gist of his message is that you don't have to be powerlessly overwhelmingly "busy". You can re-engineer your life to do what you want to do.