Until today I'd only heard of OpenSSL and GnuTLS.<p>Wikipedia lists: Botan, cryptlib, CyaSSL, GnuTLS, MatrixSSL, Network Security Services, OpenSSL, PolarSSL, Schannel, Secure Transport and JSSE.<p>I'm curious to see how much "market share" OpenSSL has given the recent bug, and what kind of operations specifically DO NOT use OpenSSL, in favour of another implementation.