Atlantis is a PBEM Game engine which is used to create many different strategy wargames today and for the past decade. This project is a large community effort.
We have released the version 4.1.0 of the Atlantis 4 game engine. Have fun.
The good news is that Anthony Briggs stepped up to be the new project admin and actually do something about this project, bring the source code over under the subversion here and bring Atlantis PBEM back to life. Let's hope in a brighter future...