[solardev]

The Straight Dope Message Board, https://boards.straightdope.com/

Smart people from a wide variety of fields, high quality discussions on many topics, and good moderation. Been a member for like twenty years and it's always been informative, insightful, and sometimes even compassionate and supportive. A pretty tight knit place with many long-time regulars.

It's much higher quality than reddit, about as intellectual as this place, but broader in focus and a bit more civil, I think. If you join, be nice :)