The Guardian has the best conference-festival-hack-day-event, it's due this time next week. The conference-festival is South by South West, the hack-day is a way to bring people together to make stuff for following SXSW, and the 'event' nature of it all means that contributors have to be focused for those two days.
And there'll hopefully be a legacy too: tools devised on 12 and 13 February 2011 will be available for future events, hopefully for anyone who wants to make use of them. It's not dissimilar to the work Mark Coyle (from the BBC's Olympics coverage) talked about during the EventScotland conference just before Christmas. In both cases the event is a catalyst for new ideas to be generated, put into practice, tested and refined. When the next opportunity to use them comes along, whether it's another conference or the 2014 Commonwealth Games, they're sitting on the shelf ready for further development.