Welcome back! I found a number of great sites over the holidays. First on the list - PBS Nova has a number of their episodes available to watching online as streaming video. Currently, there are 11 episodes available including the Elegant Universe and Life's Greatest Miracle (update to the Miracle of Life...trust me, you've seen it). Also check out the NOVA special on Katrina and the 4 scienceNOW episodes.
PBS was smart to divide the episodes into chapters, enabling quick loads even with a slow internet connection. The shows are also available in Quicktime, WMA, and RealMedia formats.