The Internet Archive is really very cool. You can spend hours checking out the Crazy fifties horror movies, Driving safety films from the thirties and the conditions of public dance halls in 1910 Chicago. You want some live music? How about Glen Phillips or Camper Van Beethoven? And of course, the Internet Archive is 36% composed of Grateful Dead.
But what I'm downloading at the moment is this - episodes of the Computer Chronicles TV show from 1984. 1984 man! Best year in computers ever? It's possible.