AWS Lambda - Automatic, event-driven compute service
Google App Engine - A powerful platform to build web and mobile apps that scale automatically.
Now Platform - Get native platform intelligence, so you can predict, prioritize, and proactively manage the work that matters most with the NOW Platform from ServiceNow.
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.
Dokku - Docker powered mini-Heroku in around 100 lines of Bash