If you have Trapcode From, Trapcode MIR and an extra 5 minutes, you should check out Peder Norrbys Nebula Construction Kit.
The Kit is basically an Ae project file that has all the controls and set up to allow you to experiment and create stunning nebula effects within After Effects.
The Nebula Construction Kit is available as a free download, just head on over to Trapcode for the Nebula Construction Kit here.
