Tom Mueller, one of the founding employees at SpaceX, explains the basics of the Merlin Rocket Engine. The current model of the Falcon 9 uses nine of these, thus the name. While the talk doesn't reveal anything beyond basic rocket engine designs, he does give some interesting numbers such as system pressures at different points within the engine. This was originally broadcast as a Livescribe pencast, link: http://www.livescribe.com/cgi-bin/WebObjects/LDApp.woa/wa/MLSOverviewPage?sid=n7SMWV6PdG7r