Richard Feynman did it before Stephen Hawking
I am driving back to San Francisco from Santa Barbara in a few minutes but I want to get this down while it's fresh in my mind. I just had breakfast with Alan Lightman, a delightful Southern intellectual, and equally delightful Marsha Bartusiak (both from MIT). We were discussing Phil Morrison, Bethe, Salpeter - old days at Cornell. It got around to Hawking and what he will be remembered for. Then Alan Lightman, author of "Einstein's Dreams" told us the following "narrative" (big theme at Kavli meeting hosted by David Gross, who actually is a GOOD ACTOR. He did a scene as Feynman in QED - good job.
In 1972 before Hawking came out with the Hawking radiation formula. Feynman was meeting with Kip Thorne's grad students, Bill Press, Saul Teukolsky & Lightman. They discussed a recent calculation of shining light on a rotating black hole and getting more energy out then in at expense of decreasing rotational energy of the hole. They all went back to Lightman's office. Feynman said: "Hey this is like stimulated emission. So he went to black board and did a A & B coefficient model and then when angular momentum J of the black hole J -> 0 there was still "A" spontaneous emission and it was the later Hawking formula!
A maid erased the board that night before Lightman and the others realized they should have written down what Feynman wrote. Not even Feynman thought it was important enough to write a paper about apparently.