Basically what you do is take every pixel on the screen and apply the following rules:
1: Any live cell with < 2 neighbours dies of loneliness
2: Any live cell with > 3 neighbours dies of overcrowding
3: Any dead cell with exactly 3 neighbours is bought to life
4: Any live cell with 2 or 3 neighours remains unchanged
Note: births and deaths can occur during 1 generation
More information can be found here: http://en.wikipedia.org/wiki/Conways_Game_of_Life
Simply put, you can make patterns that evolve into stuff

Sounds easy enough? But testing the 8 surrounding pixels for the 6144 pixels on the calc screen isnt ever going to be lightning fast. Iambian came up with an implementation a little while ago that involved some genius shifting and such, and he managed to get things running at a decent speed.
For some reason he mentioned it on IRC, that he would like to see it faster but didnt know if that was likely. I couldnt get this conway's thing out of my head so i had a go. With the aid of some page-aligned LUT's and some optimising i managed to get an implementation going. Making me happy that it actually works, and even happier that it runs at a decent speed.
I slapped some PIC loading in and a cheap titlescreen and it seems to be all done. I was just wondering if anyone wanted to test it for me? Just indicate in this thread if you do, state your email address and i will send it to you.
Screenshots:

