  This note presents a quantum protocol that demonstrates that_weak_ coin
flipping with bias approximately 0.239, less than 1/4, is possible. A bias of
1/4 was the smallest known, and followed from the strong coin flipping protocol
of [Ambainis 2001]. Protocols with yet smaller bias, approximately 0.207, have
independently been discovered [Ambainis 2001, Spekkens and Rudolph 2002]. We
also present an alternative strong coin flipping protocol with bias 1/4 with
analysis simpler than that of [Ambainis 2001].
