Every Christmas, on the same Late Show episode where Dave and Jay Thomas try to knock the meatball off of the Christmas tree, Paul Shaffer does his impersonation of Cher singing "O, Holy Night." He didn't do it last night on the show, but he did do it, and CBS has it as a web exclusive.

By the way, Thomas didn't even get to throw a football last night. Dave knocked the meatball off before he could even get a football in his hands.

[Watch clips and episodes of The Late Show and other shows at SlashControl.]