This document provides an overview of VMware's ROI/TCO calculator for analyzing the costs and benefits of virtualizing server infrastructure with VMware vSphere. The calculator allows users to model various scenarios including expected future savings, past realized savings, or a mix. It covers areas like server hardware, storage, networking, power and cooling, administration labor, and downtime. Users work through a series of modules, entering configuration details and selecting VMware products. The calculator then produces estimates of return on investment, total cost of ownership, and payback period.