GAE - Google App Engine
The Google App Engine (GAE) is a development environment that enables developers to build Web applications on the same scalable systems that power Google's own applications.
Using App Engine, developers upload an application and it's ready -- there are no servers to maintain. Apps can be served from your own domain name using Google Apps or using a free name on the "appspot.com" domain.
Google App Engine supports a number of programming languages including Java, Python, Go and PHP. Developers can design scalable applications that grow from one to millions of users and every Google App Engine application has enough CPU, bandwidth and storage to serve around 5 million monthly page views for free (additional resources can be purchased).