Just his music!
Billy Joel confirmed that he already signed off on a Glee episode featuring his music!
"All I know is I said, 'Yeah! Go ahead. Use my stuff," he says. "I was in a chorus when I was in high school, why not?"
Joel's "Piano Man" was already used in the show, but will the Piano Man himself be making an appearance at McKinley High?
"No," he says. "I'm just not a big TV actor type of guy, I'm a piano player."
Good for him — everyone and their mother is going to guest star on Glee anyway!
[Image via WENN.]