This is impressive and beautiful act of creation. Someone calls into NPR, sings a phrase of a song, and then classical pianist, Gabriela Montero, improvises. Click here then click the "Hear the Session" speaker icon. Will take you Bach.
All Montero improvisations on NPR can be found here, for now. She even tackles "Take Me Out to the Ballgame," our baseball game war horse. I hope you enjoy it.