Watch the best bits of Elon Musk's SXSW talk

Elon Musk took the stage about 30 minutes late at the Moody Theater in downtown Austin, Texas, and when he finally appeared, the sold-out crowd cheered and jumped to their feet, smartphones glowing. His conversation at SXSW was a surprise, announced late the night before, and the talk itself was just as casual. Westworld co-creator Jonathan Nolan took pre-written questions from the audience and asked Musk for his thoughts on a vast array of topics, covering everything from colonizing Mars to the benefits of a carbon tax and the future of artificial intelligence.