From Cory Doctorow:

This 1972 documentary entitled “Computer Networks: The Heralds of Resource Sharing” covers the early years of ARPAnet, the precursor of the Internet, through interviews with the heroes of the internetworking revolution. Tightly wound internetworking geeks like the legendary JCR Licklider intensely recite the benefits that internetworking will shortly deliver, sliding in digs at the telecoms industry, the Bellheads who have no desire to see this future realized. This is a fantastic 30 minutes of paleo-nerd memorabilia.