Data analysis software
FSL
FSL(Oxford Centre for Functional Magnetic Resonance Imaging of the Brain Software Library) is a library of image analysis and statistical tools for FMRI, MRI and DTI brain imaging data. Runs natively on Mac OS X
AFNI
… Runs natively on Mac OS X, other Unix systems and Linux.
NeuroLens
This Mac OS X-only fMRI analysis environment was created by Rick Hoge. “It is intended to provide extremely fast and flexible image processing, via an intuitive user interface that encourages experimentation with analysis parameters and detailed inspection of both raw image data and processing results. All processing operations in NeuroLens are built around a Plugin model, making it easy to extend its functionality.” An (older) report about NeuroLens can be found at the Apple Developer website
Freesurfer
… Runs natively on Mac OS X
Brainvoyager
… A commercial programme, runs natively on Mac OS X
SPM
SPM (statistical Parametric Mapping). Is a free programme which runs under the (commercial) Matlab. Unfortunately, Matlab will not be available for the new Intel Macs in the near future (see this discussion).