Yes, I've looked around and this seems like the best for me yet. It looks mature and not simply a clone. I'm surprised how I had missed it all those years, to be honest. Considering Hubski and a bit of Hacker News for the most part. (and first post, so hello!)
You're right about Hacker News part - that's where hubski originally came from, way back in the day. The site started being built before reddit was open source enough to clone it, although even if it had been, it probably wouldn't have been used. From there it's been hacked on, rebuilt, hacked on some more, new features added and so much more. It's its own little monster now. Glad to have you, jug. Cheers, and hope you see you around. There's a screenshot in this thread of what hubski originally looked like - check it out. You can see the Hacker News in it there.