Some are interviews with Mr. Cray, others are video recordings of speeches he gave. I believe there is a "story of his life" video too. All are worth watching.
One story I particularly liked was about how they tested the circuit boards for the liquid-cooled Cray 3, an all gallium-arsenide supercomputer that was far ahead of its time.
The circuit boards generated so much heat that they could only operate continuously when submerged in Fluorinert coolant. This of course made it very difficult to attach scope probes and logic analyzers to the various signal pathways.
The solution was a test stand that could run a board in air, but only for one millisecond at a time. The engineers would set up test vectors, then press a button to run for a millisecond, during which time the board would execute something on the order of a million clock cycles worth of processing.
Yep, that would do it... wow.