Just my $0.02...
-- I like the basic idea
-- I like the idea to leave a space at the bottom for a user name to be added at the determination of the individual (I think a Sharpie would work)
-- I like the idea of
www.fordbarn.com on it
-- Instead of "User" at the bottom (with it's inherent negative connotations), I'd suggest "Member" at the top...
I may not be able to make Oshkosh - but would still be interested in getting a couple of buttons (or stickers [hint, hint]; or both)...
Great idea!
To visualize...