There have been several interesting talks at Google that recently were published on Google Video.
They take a long time to watch, but I enjoyed a bunch of them. Among my favorites was the informative (but troubling) "A Googly MySQL Cluster Talk", Brion Vibber's "Wikipedia and MediaWiki", and Barry Schwartz's excellent "The Paradox of Choice - Why More Is Less".
[via Nathan Weinberg]
Update: If you want to see any future Google TechTalks as they are published, it appears an RSS feed is available. Not sure if that is supported by Google -- they don't link to that feed anywhere -- but it seems to work fine.