Have you heard of the new trend in conferences called unconferences? An unconference has a loose agenda, no set speakers, no canned Powerpoint presentations – just a bunch of attendees who really want to get the most out of the conference as they can, so they participate in the planning of the unconference in terms of what topics to cover and the content of the sessions. It starts off with a wiki before the unconference. The wiki is used to flesh out the agenda, the topics and so forth and then at the unconference will break into groups, side rooms and start sharing information, collaborating, discussing, case studies, etc.
I have heard it said that the best part of a conference is the discussions that go on out in the corridors between sessions. An unconference turns those corridor discussions into the conference itself. So far, there have been only a small number of unconferences — the most famous of which being BarCamp — but none that I know of on any Changing the World type subjects like environmental issues or social issues etc.
I would love to see organizations such as Greenpeace and United Way etc. organizing unconferences, or even just individuals on topics focused on making the world a better place.