I rolled my own because I had unreasonable expectations:

* Cost almost nothing even if massive traffic (I wish)

* Infinate scaling

* No markdown, just html

* Post from browser, no publishing utils

* No web server

* No database

* Important plugins - comments, social media, email list

* Templates (eventually)

Built with jquery, S3, Cloudfront

Finished but not tested, demo at https://jamackinnon.com