Visualizing the free surface with 3D volume of fluid
 

I have, what should be a very simple question, but I can't find the answer in the tutorials/manual. How do I get a visualization of a 3D two phase flow (calculated with VOF) that looks like this: http://www.youtube.com/watch?v=pNyzw...fuxCs5pV3dctDg

In other words, where I only see the free surface, but not the phases.