Billy Currington received what might just be the compliment of a lifetime from a guy who doesn't pay too many compliments -- David Letterman. "This song is absolute perfection," the late night comedian gushed of 'People Are Crazy,' Billy's No. 1 hit single that he performed on 'The Late Show With David Letterman' on Tuesday.

"This song will change your life," Letterman continued. "You're not going to do any better than this song here. If I were the people running country music, I would shut it down now."

Watch video of Billy's 'Late Show' performance (with Letterman's glowing commentary!) after the jump.