In Harry Potter, the public's way to the Ministry of Magic was through a call box. I thought that it was inspired by Dr Who, but maybe J.K.R. had the opportunity to see a bit of Buster Keaton in her childhood? After all, my childhood had Stan Laurel and Oliver Hardy.
http://www.youtube.com/watch?feature=endscreen&NR=1&v=JzZYZj0i3Og