When I am designing a typeface, I will often branch-off in seemingly random directions. These branches often produce viable avenues and get incorporated in the the main “trunk”, yet each branch is often saved as it own file.  With this handy plugin I can easily, and visually, track these branches without wandering “did I save that new eszett in ‘filename_1a.vfb’ or ‘filename_2d.vfb’?”  This little plugin simply eases the file management portion of my workflow.

Also note the progression on his Glyphs drawing app.  I’m not a beta tester for it, but it does look sweet.