Real Food Summit last September. The talk was free for a few days, but to listen to it now you have to purchase the whole summit for $99.
If you do that, I get a cut from it, but it's well worth it if you have
the money since it includes 27 talks and a whole bunch of free bonuses.
For those who don't want to pay for it, or just prefer something
written, here's the fourth post in the series, over at Mother Nature Obeyed: