TechNet Spotlight features videos of many presentations from our TechEd conferences. Here are some of mine.

• It's 11:00 PM, do you know where your data is?
  IT Forum: TechEd Europe, November 2007
• The fortified data center in your future
  TechEd US, June 2007
• Windows Mobile 6 security in depth
  TechEd US, June 2007
• Making the tradeoff: be secure or get work done
  TechEd US, June 2007
• Defending layer 8: how to recognize and combat social engineering
  IT Forum: TechEd Europe, November 2006
• Windows Vista firewall and IPsec enhancements
  IT Forum: TechEd Europe, November 2006

All of my videos on TechNet Spotlight
There are older videos, too, including a four-part security basics series with Jesper Johansson.