Recommended and mentioned products
Heroku that runs in your own cloud
Docker powered mini-Heroku in around 100 lines of Bash
I've self-hosted Dokku on Digital Ocean before with decent success: https://github.com/dokku/dokku. It's pretty nice for the scale of pet projects.
A year ago, I described a strategy we use to build Convox: Integration over Invention. This philosophy leads us to build a platform that integrates existing cloud services instead of building custom software.