http://en.wikipedia.org/wiki/Police_box
See the picture partway down. Scottish police boxes were apparently red.
Would be cool for the Master's Tardis.
That's odd. My wife took s trip to Scotland a few years back and has a picture of herself standing next to a blue police box.
She tried to open the doors but couldn't get in. I told her next time to take my Tardis key with her and try it.
Glasgow police boxes were all red up to a certain point, the 1960s I think. As well as the one in the old Museum of Transport which was mentioned above somewhere, there was
one remaining red box on Wilson Street in the city. This was restored a few years ago (complete with phone and first aid kit!) and is
now blue. I believe its also the only box of the four remaining on the streets in Glasgow that hasn't been turned into a kiosk selling coffee, ice cream or tartan(!).
By the way,
here is the current modern incarnation of a police box. I walk past it every morning and don't think I've seen it work yet.