So I stumbled upon greatness today...
Long ago there was a contest for which the entrants needed to submit a depiction of "robotfindskitten." The details of this contest are not important (and can be found elsewhere) although it should be told that most entries (2 out of 3) were images of a robots annihilating kittens.
BUT! We care not of these lost images (okay, maybe we care a bit... but that's not important right now.)
One person, Leonard Richardson, wrote a DOS program as his submission. This "zen simulation" (as he calls) it went mostly unnoticed for a couple years until he decided to rewrite it for Linux. Under GPL, of course.
In this game, you are robot (#). Your job is to find kitten. This task is complicated by the existence of various things which are not kitten. Robot must touch items to determine if they are kitten or not. The game ends when robotfindskitten. Alternatively you can end the game by pressing esc.
"And then came a PalmOS port. And then a CGI. And then Dreamcast. And then GameBoy. And then someone wrote robotfindskitten for an empty pop can... you get the idea"
robotfindskitten has just recently been ported to the PSP.
And many more! robotfindskitten.org
You found kitten!
Way to go, robot!