Zephyr was a powerful batch processing system for SPM2. It was capable of taking a set of raw fMRI data as input and producing a fully estimated set of individual and group statistics as output. It used a graphical interface, which made it quite easy to use. It was ideal for our lab, as we could quickly train an undergrad to process large amounts of data. Zephyr could gracefully handle exceptions as well, even going so far as to correct certain issues itself. Later versions did automatic data quality inspections, examining the global mean and variance of each functional run for outliers.
Zephyr worked quite well for many years with several labs across the world giving it a try. Still, time marches on, and the SPM5 batch system rendered it largely obsolete. A legacy copy is ket here for history and the curious.