This site is now served up over https, courtesy of some helpful blog posts I found. Hosting is still provided by GitHub. The entire process was quite painless and I wish I had done it sooner.
I realize I'm being "gamified" but seeing the green https: in the address bar makes me happy.
This post had enough information (and links to further reading) for me to follow along and enable https.
Relying on a separate service for SSL complicates the site, and its another thing which can fail. I can accept these risks for my personal website, but I would probably do something else if it was for someone else's site.