In 1997, the BBC aired an episode of their science show Horizon about psychedelic drugs and medicine. Over at Mind Hacks, Vaughan reports that the entire program, titled Psychedelic Science, is now available on Google Video. From his post, which puts the episode in a bit of historical context:
The programme looks at the history of psychedelic drug research when it was still easily possible, focusing on Osmond and Hoffer's early work on using LSD in treating addiction and facilitating psychotherapy.
It's also got loads of great historical footage from the early research but also talks to the new generation of researchers looking at compounds such as ayahuasca and ibogaine, who are now the senior figures in this growing area.