Materials on robotics
Recently I learned that the well known robotics institute at the Carnage Melon University has a seminar series, such as the CISST's, but they also record the talks and make them available for everyone. There are many interesting presentations online from the last three semesters.
Also, nice shootage on da Vinci beating heart surgery is available online here, and the CTS center at USC provides further materials. For more HD surgery videos and tutorials, visit WebSurg.org!
Not exactly surgical, but interesting in general robotics the IEEE award winning Robot tutorial sites. Similarly, the article series on the EU's ICT FP7 results provide a good reading on special robotics. Springer published online the most recent edition of the famous Handbook of Robotics that gives a decent coverage on almost every field of robotics.