Thanks for the easy to follow tut!
I just downloaded PDN yesterday, and this is my first attempt at anything.
The only thing I did differently was use the Shape3D plugin instead of the Bulge effect, and added a layer below my mud image that had earth like colours.
Here's my exploding earth:
I then added it to a moonscape and made a desktop background for my system:
The full size version of this is 1680x1050 and can be Found Here
Thanks again