1. A computer-implemented method comprising the steps of: inputting into one or more computers an inventory statement which comprises a plurality of existing product configurations and a plurality of components corresponding to each of said plurality of existing product configurations; inputting into said one or more computers product configuration rules which govern assembly of one or more of said plurality of components into product configurations which include said plurality of existing product configurations; (i) applying, with said one or more computers, the product configuration rules to an excess of at least one component of at least one existing product configuration of said plurality of existing product configurations of said inventory statement; (ii) generating, with said one or more computers, a build plan for said product configurations which includes one or more of said plurality of existing product configurations and at least one new product configuration which is different from each of said plurality of existing product configurations which consumes at least one of said excess of said at least one component from said inventory statement.