Related link: http://www.nytimes.com/2003/07/24/technology/circuits/24font.html

The winner of a University of Minnesota Design Institute commission is a typeface called “Twin” which can adjust its appearance based on external factors. One demo available on the design.umn.edu site renders text of your choosing with the typeface appearance based on the current weather in the Twin Cities.

The typeface was created by the Dutch company LettError. Aside from being keen in its own right, the typeface gets bonus points since one of its designers is Just van Rossum, brother of Python BDFL Guido van Rossum and programmer in his own right.