One of the things I've wanted to do for a long time, but only got to start working on it about one year ago: A social space inspired by traditional roguelikes.
In there, you can chat with people using its own text-based conversation interface which supports both public spaces (every one you see will see what you write) and private spaces. There is no message log and there will never be. It's meant for you to engage in real-time.
In addition to this, I'm adding more areas for you to explore; there's currently a Museum of Roguelikes in construction, and in the future, I plan to allow people to build stuff.
Check it out at
https://roguetemple.com/net/ , no install required, just a modern browser. Also note there's no support for mobile currently.
All your comments and suggestions are welcome!