For anyone who doesn't know this:
If you are interested in watchig any of the Smithsonian videos in full, you can download the iTunes player for free [there's a link on the Smithsonian site], and watch any of the videos listed on Smithsonian in full-length.
The cost is about $1.99 per video. You can then keep the video on your computer, or burn it to a dvd if you'd like, to watch over and over.
It's great value!