(via https://www.reddit.com/r/random ) e.g.

• https://www.reddit.com/r/Miniworlds/
• https://www.reddit.com/r/Wellworn/
• https://www.reddit.com/r/nosurf
• https://www.reddit.com/r/SubredditSimulator/
• etc. (use API to sort/selct by members/online/etc)