From their homepage
The re:publica is one of the largest and most exciting conferences about digital culture in the world. Since its foundation in 2007, it has grown from a cozy blogger meeting with 700 participants into a wide-ranging “society conference”, with 7000 visitors in 2015. Representatives of digital culture share their knowledge and decision-making tools, and discuss the future of the information society.
link to their youtube profile
So far I can recommend:
And if you can speak german, you have to watch this.