Back when I was learning how to program as a kid in the 80's on a BBC Micro I remember playing a game called Beetls or something like that, the idea of the game was simple, the screen would show a collection of different coloured beetles and then ask how many of a particular colour there is. I remember it well because it was all that much harder by the fact I only had a monitor from an old TRS-80, the bright green monochrome display you see in those rubbish movies about hackers :)