I didn't plan to turn this macro into a t-shirt, but it's gotten so much positive feedback, that I decided, "what the heck?".
The first version was thrown together in 2 minutes, so I refined and reworked the design for the t-shirt/poster version.
I fiddled with the design of the TARDIS and used it as an outline in the background.
I also changed the text. With the macro version, I used a typeface called 'Matt Smith Doctor Who'. For this version, I constructed the lettering by hand in Illustrator using the current Doctor Who logo as a guide.