Here is another interesting take on rotary type cutting. In this case they are using a laser to cut a profile out, then turning the part 90 degrees and cutting the same profile out again.  This produces a complex 3D profile with a relatively simple 2D drawing.  In this case you don't need a rotary to pull this off, but if you took the idea further you could cut on 3 or more orientations and use the rotary to more quickly orient the part.

This is something you could do just as simply with a bandsaw.  Honestly it is not a very good match for a spindle, but it does show how thinking a bit outside of the box can give you interesting results.