Microsoft has announced the availability of the Windows Azure toolkit for building apps on the Windows Phone 7 platform.
The Windows Azure Toolkit for Windows Phone 7 is "designed to make it easier for you to build mobile applications that leverage cloud services running in Windows Azure. The toolkit includes Visual Studio project templates for Windows Phone 7 and Windows Azure, class libraries optimized for use on the phone, sample applications, and documentation."
In case you were wondering what Windows Azure is, Microsoft explains it as a cloud-computing platform that "lets you run applications and store data in the cloud. Instead of having to worry about building out the underlying infrastructure and managing the operating system, you can simply build your application and deploy it to Windows Azure. Windows Azure provides developers with on-demand compute, storage, networking, and content delivery capabilities."
The link provides you with further details on the toolkit as well as documentation on how to set up and configure the kit.