Those of you who follow the awesome
Worse Than Failiure (A.K.A. 'WTF!') - blog (and if you don't you should!) will already know about this, but if you don't I highly recommend checking out the
recent OMGWTF calculator competition.
The brief: design a replacement to windows calculator.
The result: some of the most incredibly overengineered, textbook examples of how-not-to-program you could possibly imagine.
