I remember many years ago reading an estimate that the famous geneticist George Wald had made about nuclear war. He said he figured there was a two percent chance per year of a nuclear war taking place. This amounts to throwing one 50-sided die (or a couple of seven-sided dice) once a year, and hoping that it doesn't come up on the bad side. How Wald arrived at his figure of two percent per year, I don't know. But it was vivid(Metamagical Themas, pg. 776).
The chance obviously isn't actually random, but to an outside observer, the causes that create the risk are complex enough to appear random.
So, in this spirit, we present nuke, the Random Nuclear Holocaust Generator.
nuke starts out with a base 2% chance per year of a nuclear war. It is assumed that nuclear war will destroy the world. (Make of this what you will.) Every year, the chance can go up or down by as much as ±1%. Then, the die is cast, to see if the war happens that year. If it does, you are told how many years you lasted, and the program ends. If it doesn't, you adjust the odds and roll again. And so on. To keep this from the possibility of an infinite loop, if you survive for 500 years, you 'win'.
Download the C source or the MS-DOS executable, which runs happily under Windows and Win95.
NEW: The java applet!