The classic rules are defined in the book "Cellular Automata Machines: A New Environment For Modeling"
by Tommaso Toffoli and Norman Margolus, published by The MIT Press (1987).
This page has live color exhibits of the following classic cellular automata rules:
1 Out Of 8,
2 Out Of 8,
3 Out Of 8,
Anneal,
Border/Hollow,
Conway's Game Of Life,
Brian's Brain,
Greenberg,
Inkspot,
Lichens,
Lichens With Death,
Life With History,
Majority,
Parity,
Parity Flip,
and Time Tunnel.