Selected Cellular Automata Links
Game of Life
Mark Niemiec's catalog of small objects and their syntheses from gliders.
Moving objects catalogued by period and number of live cells, Heinrich Koenig
Still life theory, Matthew Cook (see also his presentation at the MSRI combinatorial game theory research workshop).
Metacatacryst. Tomas Rokicki uses a hashlife algorithm to simulate a quadratic-growth pattern to ridiculous numbers of generations.
LogiCell implementation of Boolean logic in Conway's Life.
Spaceships in other cellular automata
Kellie Evans' Ph.D. thesis on variant life rules.
Just Friends non-totalistic rule with many interesting patterns.
Rule 3/2ab3, another non-totalistic rule with small gliders.
The Logic Rule, yet another non-totalistic rule with small photons and a nice replicator-based photon gun, allowing logic circuits to be built from glider streams.
Triangular cellular automata, Carter Bays. His rules 2,4/4,6 and 2,4,6/4,6, at least, can generate gliders from random initial conditions.
Strange Universe, gliders in a 12-neighbor triangular CA.
Hexagonal CA gallery, showing several hexagonal rules with gliders.
Hexatron. More hexagonal rules with gliders.
Gliders in rule 110, a one-dimensional CA recently proven Turing-complete by Matthew Cook.
General references
Classifying cellular automata automatically, Andrew Wuensche.
Cellular Automata - Optimisation. Interesting discussion of CA programming techniques.