Slitherine

I have played hundreds of Field of Glory multiplayer games and it's a great, though not flawless, play-by-email (PBEM) game. I've also played Panzer Corps multiplayer but was rather disappointed with it (although I do feel if it was better designed it would have the potential to be as good as Field of Glory multiplayer).

Can anyone recommend any other good Slitherine PBEM multiplayer games?

Personally I like Battle Academy but then I may be biased