TL;DR: If you install Sandstorm and choose to use a subdomain of our dynamic DNS service sandcats.io, we’ll automatically set you up with an HTTPS certificate from GlobalSign. The private key never leaves your machine and is automatically rotated every week. Details: https://blog.sandstorm.io/news/2015-10-01-free-ssl-certificates.html
I work on the Sandstorm project, which is an interface for running web apps on a server intended to be at least as secure and easy as Google Docs. Except it's self-hosted and open source, so even more secure.
I've been working over the past ~4 months on free HTTPS certificates for Sandstorm users, and it's finally live. So I thought I'd send a link here.
I'm happy to answer questions!
Cheerio,
Asheesh.