Security at scale at Google [video]
youtube.com
youtube.com
Really Google? There isn't anything else more interesting or useful to say? Sure, both of those two points are important, but I would wager a very significant percentage of people in the room (and people watching online) already know both of those points, probably already implement them, and were watching in the hopes that they glean some new useful bit of information.
GTAC 2013: Drinking the Ocean - Finding XSS at Google Scale: https://www.youtube.com/watch?v=rd5TZKRg-lc (from Google Test Automation conference).
Google I/O 2012 - Security and Privacy in Android Apps : https://www.youtube.com/watch?v=RPJENzweI-A
This one is fun to watch. (GTAC 2011: Keynote - How Hackers See Bugs https://www.youtube.com/watch?v=onpxOG3TrWg) Not technical, but good for a bus ride.