Forrester's Total Economic Impact (TEI) analysis methodology measures "not only costs and benefits but also the enabling value of increasing the overall effectiveness of business processes." (see Appendix A for more details on this methodology)
We have come across various case studies using Total Economic Impact (TEI) to evaluate the business case for infrastructure solutions - implementations, upgrades etc.
This case study uses Total Economic Impact (TEI) to evaluate the financial impact of implementing the application streaming feature of Citrix's Presentation Server. The document shows all calculations and assumptions that go into creating this business case using Total Economic Impact (TEI).