The first program you ever wrote was called Hello World

The first program you write in any new language you learn is called Hello World.

This program is a simple and optimistic little bastard that shows you how to send a string to the terminal.

So it makes sense that the last program you ever write (and the last you write in a given language) should be called Goodbye World. It should be horrendously complex and depressing, and should prove that nihilism is the only rational response to the irrational world in which we live.

Feel free to submit examples in the comments. I'm working on something...