Is this required to be in person, or is conference call/irc/email/etc sufficient? Furthermore, is it possible for board members to be reimbursed for expenses? I can see this being a major obstacle for non-us residents otherwise.
Kelly already answered the first part, but yes. If TGF has money, it's board members can be reimbursed for the expenses of attending a meeting (including phone bills, even), without destroying it's non-profit status.
-- Dan