David Fox created some interesting videos which can be found here: http://davidfoxit.com/media/
Scrum Tips for Scrum Masters with Virtual Meetings (1-2-4-all, W3)
Scrum Master Tips for spreading information (1-2-4-all, W3)
Easy but effective tips for better Sprint Planning (1-2-4-all, critical uncertainties, social network webbing)
Measure you own agility using whats important to you (shift & share, ecocycle planning & panarchy)
Tips and Tricks: The Daily Scrum (1-2-4-all)