Fireflies are examples of such oscillators and so the pieces in the game are termed fireflies.
For more complete information, see the full description of the game and the program, which you should read in order to understand the following. From most initial configurations in Flash, the fireflies will synchronize. However, from certain initial states they will instead evolve into groups which cycle stably. For a discussion and description of such cases, go to special cases. This link also leads to an example of a game which allegedly evolves in this way but which, I believe, does not in fact do so.