Here's a nice playground for a few cellular automata on a hexagonal grid:

• Game of Life
• WireWorld
• Rock-Paper-Scissors Automata

In all of these, you'll be brought to a blank canvas, where you can create your own patterns and run them as automata. Clicking in the vast space you're given will add or remove cells from the simulation and change their statuses. You can also change the speed with the slider, and do some advanced editing with the other tools at the top, as well as saving and exporting your arrangements (the export output is hidden by the little triangle until you click it).

The Game of Life one is a standard port of the classic. You can even adjust how many neighbors cause cells to survive or spawn.

WireWorld is another classic automata. This is the one I've done the most with, and it's fairly straightforward to implement various logic gates here. I've done so, and put a 'demo' menu on this page, so you can see some examples of this. There are some cool ones, take a look!

Finally, Rock-Paper-Scissors is a straightforward automata where two or more adjacent rocks capture scissors and so on and so forth. This can produce some beautiful arrangements that look like clouds of gases.

If you'd like to implement your own form of hexagonal-grid automata, check out the README file.

Just a note, this is not fast. The primary focus of this was to get something extensible and fun up quickly. I am liable to redesign this with speed in mind, but if I do, it will keep the same extensibility you find in the current version.