They story behind a PC classic, X-COM.

The first part that you see is the strategic level. As the general in charge of the “Extra-Terrestrial Combat Force,” or X-COM — the name was suggested by Stephen Hand and Mike Brunton, two in-house design consultants at MicroProse UK — you must hire soldiers and buy equipment for them; research new technologies, a process which comes more and more to entail reverse-engineering captured alien artifacts in order to use your enemy’s own technology against them; build new bases at strategic locations around the world, as well as improve your existing ones (you start with just one modest base); and send your aircraft out to intercept the alien craft that are swarming the Earth. In keeping with the timeless logic of computer games, the countries of the Earth have chosen to make X-COM, the planet’s one real hope for defeating the alien menace, into a resource-constrained semi-capitalist enterprise; you’ll often need to sell gadgets you’ve manufactured or stolen from the aliens in order to make ends meet, and if you fail to perform well your sponsoring countries will cut their funding.

X-COM

I lost a whole summer to this game. I spent hours every day playing this game and still remember it as one of the best games I’ve played.