Who am I to argue with the Great Phil Plait? As he mentioned in internet eons ago, Retail Who:

BABloggee James H.G. Redekop sent me a link to a webcomic called Retail, which did a brief Doctor Who series for Halloween. It’s not a knee-slapper, but it’s cute. Still, I think the protagonist screwed up. As much as I loved Tom Baker’s Who, it’s been 20 years. David Tennant would’ve been the way to go.

When you check it out, make sure you look at all five, up through Halloween itself.