Google App Engine - A powerful platform to build web and mobile apps that scale automatically.
Heroku - Agile deployment platform for Ruby, Node.js, Clojure, Java, Python, and Scala. Setup takes only minutes and deploys are instant through git. Leave tedious server maintenance to Heroku and focus on your code.
Salesforce Platform - Salesforce Platform is a comprehensive PaaS solution that paves the way for the developers to test, build, and mitigate the issues in the cloud application before the final deployment.
AWS Lambda - Automatic, event-driven compute service
Dokku - Docker powered mini-Heroku in around 100 lines of Bash
Kubernetes - Kubernetes is an open source orchestration system for Docker containers