The Broadwayworld newsletter, which I love receiving in my email every morning, pointed me two webcasts available from the NY Public Library. One features Broadway director Hal Prince. (In the photo above, Hal Prince (center) directing Jack Gilford and Lotte Lenya in the original production of Cabaret, New York, 1966. Billy Rose Theatre Collection (Friedman-Abeles Collection).
The other is a Master Class featuring Broadway singer Barbara Cook. For anyone who loves theatre, these are treasures.