Being theoretical constructs, existing solely in there own constructed universe, cellular automata are children of the information age. And the Internet is central to this new age, so it's inevitable that the web is full of automata and there creators. Java, gives the web the ability not just to describe the operation of the automata, but to demonstrate it. So here are some of my favorite cellular automata sites

Modern CA A truly colourful page showing a large range of automata in the psychedelic glory. A grate site to look at, but a little short on explanations.

Mirek's Cellebration A great applet to play with. Lots of parameters to play around with. Not quite so colourful, but still can produce images of amazing bueaty.

Conways Game of Life With out a dought the fastest Life CA on the web. It only does life and only in two colours, but it can do huge patterns at high speeds.

Life Pattern Catalogue A very large collection of life patterns all brought to life with Java. Lots of detail about what's going on to.