Game File: 

Pixel Colony (Windows).zip

This program will ask you to select an image. It will then turn that image into a terrain map which you use to create an island paradise. Your island will then be colonized by a ship full of pixels who will multiply and begin to convert the landscape into industrial sprawl. There is no interaction; the effect is supposed to be more like watching an ant farm than playing a game.

Some notes on performance:

I tried hard to optimize it this program, but there is still significant slowdown if you use a large image. I used one that was about 400x500 to good effect. Even then, once your island gets a large population slowdown is inevitable. I ran this on a dated laptop, though, so your mileage will vary. Theoretically, the program will keep running indefinitely even if the frame rate tanks.