Duke Ellington in 1937, Cream in 1968
How records are made, 1937 would be fascinating even if it didn't start off with a Duke Ellington recording session. It goes from the recording all the way to the application of the labels to the shellac disks.
For some reason, YouTube then suggested that I would want to see a 1968 live version of Cream doing "Crossroads", and they were right. Many of the same licks as the well-known version, but Clapton's solos really are different, and Bruce and Baker really, really kick ass.