The service where web developers can run their own web applications on the same scalable systems that power our own application on Google’s infrastructure. App Engine applications are easy to build, easy to maintain, and easy to scale as your traffic and data storage needs grow. With App Engine, there are no servers to maintain: You just upload your application, and it’s ready to serve your users.
You can even run or serve your own application from your own domain , now I hope now it sounds interesting :). You can share your application with the world, or limit access to members of your organization.
Among all, its FREE :) – App Engine costs nothing to get started. Sign up for a free account, and you can develop and publish your application for the world to see, at no charge and with no obligation. A free account can use up to 500MB of persistent storage and enough CPU and bandwidth for about 5 million page views a month. Ofcourse you have an opportunity to increase your infrastructure by purchasing the additional computing resources.
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Featured App Engine Applications