SF Bitcoin Devs Seminar: A Deep Dive with Bitcoin Core Developer Greg Maxwell (Apr 2015; lenth: 83min)
SF Bitcoin Devs Seminar: Blockchain Scalabilty with Peter Todd (Mar 2015; length: 50min)
SF Bitcoin Devs Seminar: Scaling Bitcoin to Billions of Transactions Per Day - "Lightning Network" (Mar 2015; length: 55min)
more seminars on SF Bitcoin Developers and Taariq Lewis

Money and the Development of Human Society: From Barter to Bitcoin | Mark Thornton (Apr 2015; length: 28min)

The Future Of Cryptocurrencies (May 2015; length: 12min)
(Footage shot 2014 at Texas Bitcoin Conference)



interesting ot stuff, i stumbled upon recently:
Cory Doctorow: "The Coming Civil War over General-purpose Computing", Talks at Google (Aug 2012; length: 70min)