Worried about which Doctors would and would not appear in the 50th Anniversary Special? So were some of the actors who portrayed the Doctor in the classic Doctor Who episodes. In the comedy short The Five(ish) Doctors Reboot, Peter Davison teams up with his fellow Doctors to take their rightful places in front of the camera.
Davison wrote and directed this sketch, in which he, Sylvester McCoy, and Colin Baker poke plenty of fun at themselves and the other folks behind Doctor Who. It also features some surprise cameos from outside the world of Doctor Who—and adds an Easter egg to "The Day of the Doctor." It's best enjoyed after watching the 50th anniversary special.
The Five(ish) Doctors Reboot [BBC—Hat tip to Iain!]