The following videos are played by the QuickTime Player, which
can be downloaded here for free:
Quick Time for Macintosh
Quick Time for Linux [well, really it's Crossover, but it does the job]
Quick Time for Windows
Notes for streaming video users:
If the QuickTime Player does not start automatically when the above links are clicked, it might be due to a misconfiguration of the browser. Please try start the QuickTime Player and input the link texts (e.g., rtsp://elmer.tapir.caltech.edu/Lecture6_tape1_web.mov) manually.