I've never played via VASSAL but I Host regularly PBEM games.
Really? Ever have space for another player?
I usually am restricted to only sending emails after 1900 NY time. And I've played a number of games using Cyber Board, and am familiar with the rules, but don't have a hard copy of the game. How do you do it via email? Without Vassal (or Cyber Board), how does everyone keep track of the board state?