The Grammy award-winning star discusses what he thinks about when he is picking which songs to record. Keith Urban has had his fair share of strange interactions with fans. When asked about his wildest moment with a fan during his recent appearance on "The Kelly Clarkson Show," the 57-year-old country singer recalled the time a fan threw an unexpected item on stage for him to sign. "I was playing a show, and this girl yells out from the audience, 'will you sign my leg?'" Urban explained. "And I went, 'of course' what a great moment. This was years, a long, long time ago. She's out there, I say yep come on up! Then she disappears, I couldn't see her. Then she pops up out of the same spot and throws this prosthetic leg up on stage!"