One of the classic patterns
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My avatar was created using my version of the Game of Life using this pattern and rule(note that it is not 23/3):
#D Thanks to my daughter Natalie
#D Try at cell size of 1
#R 8/1
#P -29 -29
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IMHO - as I learned Conway's Game of Life the trick wasn't writing short code, but code that could do complex life forms quickly. Using the classic pattern above and a wrapped world of 594,441 cells the best I could ever do was around 1,000 generations / sec.
Another simple pattern
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And gliders
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