Everyone is talking about the cloud and Microsoft has put up a TCO and ROI calculator for the Windows Azure Platform. Available in both online and offline form you can play with and measure the savings in development and migrating to the Azure platformproviding you with a report that gives estimated line item costs for your organization.
Entering data into the calculator is fairly easy. For a medium sized healthcare e-shopping site that requires a SQL database I entered, I was going to save $133K over an on-premises virtualized solution. If you decide to register you can get a detail estimated line item costs for a TCO and a 1 to 3 year ROI analysis.
Couple of links to help you out: