They actually did end up making a Christmas Carol episode of The X-Files, loosely based on the fifties film adaptation of Dickens' novel starring Alastair Sim, which had Scully going home for the holidays and getting wrapped up in a mystery involving weird phone calls and a little girl who may or may not be her dead sister, Melissa. Which doesn't sound a whole lot like the story of Ebenezer Scrooge, famous douchebag, getting visited by three ghosts and scared into being a better person; instead, she's somehow treated to a load of her younger selves dropping by to give her what for. It's a pretty sweet episode, all told. Originally, though, the writers basically wanted to just take the plot of A Christmas Carol and put Scully in the Scrooge role, without much change to the structure of the ghosts of past, present and future. David Duchovny was busy filming a movie nobody would see (Playing God, for the curious) so he wasn't available for filming Vince Gilligan, John Shiban, and Frank Spotnitz decided to write a Scully-centric episode. Their attempts at making Dana go full Ebenezer failed - since she's isn't a famous douchebag, for the most part - and they changed it up. We'd still like to see Scully telling an orphan to buy a big goose, mind.
Tom Baker is the Comics Editor at WhatCulture! He's heard all the Doctor Who jokes, but not many about Randall and Hopkirk. He also blogs at http://communibearsilostate.wordpress.com/