1. A clustered computational system comprising: a clustered computational engine comprising a plurality of clustered computers and configured to perform computations; a program host computer that stores, on a computer-accessible storage medium, a plurality of programs and a plurality of inputs to the programs, wherein the programs define computations that can be performed by the clustered computational engine; and a queue manager configured to periodically poll the program host computer in order to determine when the program host has stored sufficient inputs to allow the clustered computational engine to perform a computation defined by the program and to schedule the performance of the computation by the clustered computational engine.