How to create a Nebula in Cycles? I'm trying to create a Nebula walk through using Blender but my final art is unrealistic. I would like to create a realistic nebula without Image backgrounds... I used particle System and clouds, but the isn't realistic.
Any suggestion? Or tutorial?
Thans in advance.

Update 1: It seems that the best approach is using the "Quick effect smoke." I'm working on it and here you can find my first render...


Update 2: More tests. Now the background is a Ocean System and Clouds with Particle System... I think looks better...


Final Update: The easyest way is create an Ocean (via Ocean System) in Cycles render and some durst and stars (via particle System) in Blender render; and mix both scenes in Compositor. Here you can find the final render...
https://youtu.be/-Lx_U_Z3Z6s
Here's what I came up with using the ocean modifier and a volume shader:



I used a cube with a volume emission particle system to add stars:





I had planned to use a smoke simulation with the ocean objects as emitters, but a smoke rendering bug is preventing me from testing this atm..
Will update further once the bug is fixed.