This is way forward-thinking: Gnomedex is live-streaming its main sessions right now, for another day (up ’til 5:45pm Pacific Time / 8:45pm Eastern). They’ve been doing it for several years now (audio since 2006; cf. the Gnomedex philosophy)
This conference allows its non-attenders to watch it all live streamed over the web!
See the schedule to catch the segments of most interest to you.
Does live-streaming discourage people from attending and having to pay registration fees and travel costs? Nope, still sold out! Gnomedex is on my short list of conferences I really want to go to.
Know of any other conferences that are (partially or entirely) live-streamed? Interviews don’t count.