Everybody seems to be doing zombies. I mean, there's a Jane Austen zombie thing out there somewhere.

BBC are probably a bit fussier about crossovers than Paramount are... back when Marvel had the Star Trek licence there was a Star Trek / X-Men crossover comic (which wasn't actually that bad, all things considered, but then I'll forgive a lot when the comic includes some classic confusion between two very... different... Dr. McCoys...)

Oh yes. I can't think of many official Doctor Who crossovers. There's the New Adventure with Sherlock Holmes...

There was a book that read like really badly-edited fan-fiction, too.

Ahahahah. It's Abnett and Lanning. THOSE BOYS. They always have had a thing for insanity. =D

They've both worked on all four properties before too! Should be a cool series. *makes note to track it down when the trade comes out*

Hehehehe!