[ekidd]

As github pages, technically are virtual domains, they share the same ip with many other pages, if you want to support https, you need to serve either each page on a different ip (not free), or they need a to configure multidomain ssls

If you use SNI, you can serve multiple SSL-protected domains from a single IP. Happily, this is supported by 97.6% of web browsers these days: http://caniuse.com/#feat=sni In fact, most browsers which don't support SNI have been end-of-lifed and are no longer receiving security updates. So unless you still need to support Windows XP or Android 2.x, you can now generally host multiple SSL-protected domains on 1 IP address.