The incremental cost per unit of performance of a variety of flexible system functions has been sharply reduced through the application of a high degree of functional parallelism with serialized arithmetic. (Functional parallelism as used here is the parallel use of an array of high density, low cost, lower performance devices to obtain a high performance function.) System functions, such as fast Fourier transformers, digital filters, graphics function generators, and matrix computational arrays have all been reduced to a form which is highly channelized in this manner. Such computationally intensive digital signal processors employing novel computational means are shown to promise a reduction in size, weight, and power by an order of magnitude over conventional techniques. Several examples of modular functional processors are presented for which the algorithmic formulation, architectural configuration, and prototype implementation are described.