From wikipedia:

David Amram (born November 17, 1930) is an American composer, musician, conductor, and writer. As a classical composer and virtuoso performer, his integration of jazz (including being one of the first noted as an improvising jazz French hornist), ethnic and folk music has led him to work with the likes of Thelonious Monk, Dizzy Gillespie, Willie Nelson, Charles Mingus, Leonard Bernstein, Sir James Galway, Arthur Miller and Jack Kerouac throughout the course of his career.

This performance was totally spontaneous, he just sat down and started playing, and I couldn't help but join in. Since I'd never played with him before I was pretty nervous (and I mean come on, look at the list of people he's played with), though throughout the jam I started to loosen up and you can hear how my initial rigidity starts to fade. Also, I should've closed the lid on my piano first, since it's more "tinny" than the other one--that and my nervousness led me to sometimes overshadow his immaculate touch. Regrets aside, it was quite a treat! We also recorded some other numbers as he brought out numerous exotic instruments. I wasn't able to get it all on my camera, but someone else did, so hopefully they'll be up on youtube later on if anyone's interested. One in particular was spectacular: I backed him up playing take the A train while he played 2 pennywhistles simultaneously!

This was a real treat, and I hope you all enjoy!
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https://www.youtube.com/watch?v=OpP40gBx6KI