Controlling Your Testing Costs with Windows Azure
Windows Azure is based on an Operating Expense (OPEX) billing model as opposed to a Capital Expenditure (CAPEX) billing model. The implication of OPEX is that you do not have to expend capital to buy hardware and software or to pay for support staff to maintain it. That is the good news.
The (potentially) bad news is that “In Windows Azure you are billed when you deploy, not when you run.