I don’t mean former versions of Superman like the Golden Age Superman, or Pre-Crisis Superman or New 52 Superman. I mean versions of Superman that were never meant to be the mainline version of Superman like the Red Sun Superman, American Alien Superman or Kal-L of Earth-2 (who was not the Golden Age Superman, but rather a creation from the mid-1960s).

Mine is probably the Calvin Ellis President Superman that Morrison came up with. He's got so much potential. He's similar enough to the main Superman to be recognizable as Superman, but there are just enough small tweaks that make him different in really interesting ways.