First blog that comes to mind is Jai's old one. A fair number of rationalist memes began there, I think, but it disappeared at some point. I'm not sure if it was rehosted elsewhere or what.
Not sure of the title. The tagline was "almost no one is evil; almost everything is broken." The address was http://blog.jaibot.com. Some specific essays originating there were "500 million, but not a single one more," "Foes Without Faces", and "The Copenhagen Interpretation of Ethics".
3dirk
It's been moved to https://laneless.substack.com/ .
Also posted the question to r/slatestarcodex.