John Horton Conway's Game of Life, including complete lists and glider syntheses of smaller still-lifes, oscillators, and spaceships. http://home.interserv.com/~mniemiec/
Eric W. Weisstein's home page about Conway's Game of Life and related CA. Tutorial, information, patterns, links, references. http://www.treasure-troves.com/life/
An artificial life implementation using GNOME as its front end. Like "Conway's Game of Life' but with a totally different ruleset. http://sourceforge.net/projects/glife/