Make it easy to publish spreadsheets on the web
Excel should easily integrate as a computation engine into a web backend so that spreadsheets can be published. Numerous spreadsheets exist in business that take advantage of Excel's formulae and computations. It would be beneficial to have these available through web interfaces. For example, someone should be able to post values that are entered into cells and then trigger Excel's solver to output a solution that is read from another cell(s) and returned as the result.