A: Windows Azure has introduced an Infrastructure as a Service (IaaS) capability that allows virtual machines (VMs) to be hosted in the Windows Azure cloud. Pricing is based on the number, type, and size of VMs that are provisioned (whether they are running or not) in addition to storage and bandwidth requirements.

Microsoft has a great calculator at its Windows Azure site that lets you enter the number of Windows and Linux (yes, Linux is supported) VMs along with other parameters to estimate the monthly price (see screen shot below).

Windows Azure Pricing