Oh I like this idea for a contest, especially if matadorx is giving the question so can't win......and I ask that the all incarnations of the doctor back to the 1960's included, yea anything to increase my chances of winning a tank....as long as I don't have to hang out in cardiff.
It would be fun, but the only problem with that is that the winner would be the one who googles the answer the fastest
and Im not sure there's enough Who fans out there to make for a good contest...