phalanx computes a digest of many buffers simultaneously, and produces a combined hash of them all. It is an initiative to provide a fast, simple, and portable alternative method to compute a checksum in a parallel fashion. It has options for I/O buffer size, hash width, number of threads, and more. It can be run single-threadedly for performance comparisons. It can check files against previously-saved sums, like "MD5sum" does. It also has a "demo" mode, to ascertain accurate operation. It is intended to be useful on large files and multicore/multiprocessor/multithreaded environments.