Some considerable time ago I created a toy example of fixation based on the MandM example given by Allan Miller. For various reasons that stopped working (argh, browsers!) so I’ve re-created a slightly different version.
The original OP is here: http://theskepticalzone.com/wp/?p=3877
Instead of displaying each individual MandM we see a count via a pie and line chart plus the generation each color was made extinct in.
Some of the comments/requests on the original OP are still on my to-do list with this. Currently the starting state (number of each color) is fixed in advance.
Eventually the source code will be published. If this does not work for you it would be useful to note your OS/Browser in the comments.