Costs estimations and planning
Cost estimation is a complex subject because Cloud service providers, by nature, have very detailled pricing grids. So you need to make a very good estimation of your detailled usage to be able to perform an estimate.
On top of that, the variability of your workloads or the variability of the traffic on your apps make the usage a non-trivial thing to describe.
An API based solutionWe offer an API that compute a cost estimate based on a usage description you submit. Using this API, you can estimate how much each different variation of your load would cost. And by making repetitive call to the API, you can estimate how much a certain usage pattern would cost over a given period.
Yes, it a low-level, quite geeky solution. But it's very powerful and you can call it from Excel. Now that doesn't sound too geeky :-)
For Windows Azure estimations, we will soon release a solution based on the Azure RateCard API that will help estimate the cost on Azure of current AWS and Google Cloud deployments.