Peter Jackson

 portrayed himself in a cameo for the 50th Anniversary story The Five(ish) Doctors Reboot.

Jackson is an award winning feature film director, best known for the highly acclaimed The Lord of the Rings and The Hobbit film trilogies. He can also be seen in cameo roles in most of his films, as well as in Edgar Wright and Simon Pegg's Hot Fuzz. Jackson's cameo for Five(ish) Doctors Reboot was filmed with Ian McKellen on the set of The Hobbit trilogy in New Zealand. The films feature Sylvester McCoy in a supporting role.

Jackson also helped to found Weta, a design and special effects company which, in 2010, designed the Eighth Doctor's wooden-handled sonic screwdriver. 

Possibility of Directing
Jackson has admitted himself to be a die-hard fan of Doctor Who, owns two classic Daleks, and in 2012 began to express his interest in directing an episode of the series; “Just name a time and place, and I’ll be there!” The following year it was stated that discussions are "actually kind of serious".

In November 2015 Jackson released a humerous video on his facebook page entitled Home Invasion, in which he discusses Steven Moffat's requests for him to direct an episode of the series. The video also features Peter Capaldi in character as the Twelfth Doctor, and a Dalek.