I'm trying to create a private slack community for this actually. It's just a bunch of friends/trusted people who we know are smart, bring a new perspective etc and have good things to contribute. It's been slow going creating a community like that (high achieving, smart people who are usually too busy to participate - So far we're just 20 people with like 10 the most active) but I have hopes that some day it'll become good enough that I can open it up to the public.

Things we usually discuss (and we have at least 1 person who is more knowledgable/an insider so they can teach others and give context) - Tech, Economics, Geopolitics, Culture, Cinema, Photography, BioTech/Energy etc. The goal is _in depth_ discussions, not just water cooler commentary. But since it's friends, it also becomes your usual facebook chat replacement occasionally.

I know it's not the answer you're looking for (since it's actually private/friends and their friends etc for now) but just thought I'd mention this in the context. Trying to create and maintain a community has been an interesting experience so far. :)