We missed it this past summer when Schneider Optics released a Photoshop plug-in, which the company calls the B+W Software Filters, comprising two sets of filter effects.
Among the effects in the two sets are graduated neutral density, polarizing enhancer, soft focus, and warming filters.
The B+W Software Filters plug-in is available for Photoshop 5.5+ on Windows 98+ or Photoshop 7.0+ on Mac OS X+.
A demo version of the plug-in is available for download, but a fully licensed copy must be purchased from an authorized B+W retail dealer. No pricing is given on the Schneider Optics web site.