Bill Murray was in Washington, D.C. on Sunday to present David Letterman with the Mark Twain Prize for American Humor. While he was there, he used his celebrity for a little good.

The paparazzi spotted him signing autographs for fans, but not for free. He was signing in exchange for donations for Puerto Rico and was charging a $20 minimum.

If you ever go to any celebrity conventions that take place every month across the United States, then you know that 20 bucks is a bargain, especially for a guy of Bill's caliber.

One guy tried to hand him three bucks, and he wasn't having it. Mr. Murray said, "Three dollars? Go get a job and come back."