ConwayLife.com

https://www.youtube.com/watch?v=QWE7f07kfC0

It looks like a ruler forms in Brian's Brain. It starts off with repeated two cells that are fairly symmetric. I paused it shortly after forming, and you can see repeated 4 sided stars that are also fairly symmetric,

This one looks better: https://www.youtube.com/watch?v=SDijAkKmAwI

This one makes better sense: https://www.youtube.com/watch?v=JrY389BnHx0

Just a general tip -- it's better to post patterns (in RLE format and between code tags, ideally) than to link to Youtube videos. The former make it possible for others to play with and investigate what you've found; the latter... well, don't.

It's also generally a good idea to not start new threads if there is an existing one devoted to whatever you're talking about. Brian's Brain has its own thread; otherwise, Miscellaneous Discoveries in Other Cellular Automata is also a good thread to post to.