This site is as simple as it gets. You click the button and a random prediction on how and when the world will end is generated for you, including a shareable URL.
The way it works is that it will choose a random category and then send messages from a list within that category in a sequence that makes a little sense... This creates a weird timelapse of events which lead to the destruction of the world. It is far from perfect, but was funny to me at the time.