Are there any tips or rules of thumb to getting the dynamic calculations to run faster?  I have noticed the more I use dynamic cloth that the simulations can run for 20-30 minutes, even on my 6-core Phenom II.  I leave the cloth settings pretty much stock, except sometimes drop the collision offset and depth to .5 to get better results.  I even went so far as to export a cloth item as an .obj, import it into Max, optimize the mesh from several ten thousands of vertices down to around five thousand, but that didn't have much effect.