Today's funny ha-ha in a ho-ho weird way video comes from Funny or Die, where Owen Burke convinced Will Ferrell and John C. Reilly to re-enact the famous Christmas duet by Bing Crosby and David Bowie, recorded just before Crosby's death in 1977.
They're fairly faithful to the whole segment, save for an additional NSFW remark or two. If you're not yet in the holiday spirit, perhaps this is just what you need to be reminded 'tis the season. Roll it!
And for comparison's sake, here is the original 1977 video.