MathOverflow will be down for maintenance for approximately 3 hours, starting Monday evening (06/24/2013) at approximately 9:00 PM Eastern time (UTC-4).
show/hide this revision's text 1 [made Community Wiki]

First thing I thought of was the Princeton oral history project about math in the 1930's:

however they don't seem to have the audio online (just transcripts of the interviews, that are still very interesting). I wonder if the audio tapes are accessible at the Mudd library or elsewhere.