This is a simple app which sits between S3 and your users. Push this war to a service like Elastic Beanstalk, a service which does allow you to specify your own certificate, and voila! You now have CNAME friendly HTTPS with the simplicity of S3 file management. Isn't that easy?
It's a simple, effective toy project – solves an esoteric problem and demonstrates a super simple web application and consuming the AWS Java SDK in clojure. What more could you ask for? I don't know either.
Enjoy! If it breaks or runs too slow, well, patches are always welcome.