RetroHexChat
Every channel opens onto a Space, a pixel-art world. Everyone in the channel can walk around in it together. Make a character, then go in and chat. What you type shows up above your character and in the chat. Everybody arrives on the island at the End of Time.
Through the gate there is an empty white floor. Choose furniture, plants and games in the Build menu and place them anywhere. Your buildings stay in the channel, and everybody can see them.
Inside there are arcade games and a pool table. Each machine opens the games of the channel.
Inside there are work desks and a meeting table. It is a place to meet and to talk about work.
Each channel has its own Space, and so does each private conversation.