Wisdom 2.0 - February 14-16/17, 2014 in San Francisco - http://wisdom2summit.com/
I posted a few articles on Wisdom 2.0. Good place to see how meditation and Buddhism is adapting to the 21st century in the West. I attended their small conference in NYC a few months ago and will be attending this big one next year. They expect 3,000 people. Controversial in the Buddhist world. The entire conference will undoubtedly be streamed live on the web - probably free, but there may be a small charge, so you certainly don't have to go to watch the presentations.
Buddhist Geeks - Oct 16-19, 2014 in Boulder, CO - http://www.buddhistgeeks.com/conference/about/
This conference is also streamed live, less expensive than Wisdom 2.0 and more tech oriented. As I posted elsewhere, you can listen and download BG podcasts free - through iTunes. They also conduct teachings and retreats on-line. Probably videos of this year's conference are posted on line. Some good talks and discussions, but I felt their panel on "scandal" was a mess.