My personal favorite has to be the one I made in x86 assembly ~30 years ago. I didn't know about hash life at the time, but still, it ran pretty fast. I seem to remember I used page flipping and moved the start of video memory each iteration. Or something like that.
FWIW, Golly (mentioned elsewhere in this thread) implements Hashlife as one of its core algorithms. So you can use it to simulate enormous patterns at enormous speeds, as long as they are sparse and/or regular enough that the hash hit rate is high.
https://en.wikipedia.org/wiki/Hashlife
My personal favorite has to be the one I made in x86 assembly ~30 years ago. I didn't know about hash life at the time, but still, it ran pretty fast. I seem to remember I used page flipping and moved the start of video memory each iteration. Or something like that.