We have letters in Ditto, but we're working on https://armada.buzz if you're interested. https://armada.buzz/invite/naddr1qvzqqqyzz5pzqqhllgzkurfdwaf4hjggdjtcvppqa6ugj3pfspeq0jtjh3drgqjmqqqqgzqqq9#BAACAwRysYEIcGnu4mENv5J-RHBc