Thought you might have that one for reference already :-)

I'm still in the pitch black... without Riddick's extra senses when it comes to the mat room tbh!

Something with the 3d clouds node maybe?

Is it maybe the edge_blend node that could be used to distribute the blue to the outer parts?

I've been trying to get patterns of rust more around the edges of a mat zone on something I've been playing with... I'd been going down that route. But not got anywhere that useful with it yet. Probably because that isn't what that node is meant for. LOL ;-)

Anyway, just found this post...

http://forum.runtimedna.com/showthread.php?69734-Bone-shader-and-glowing-orbs&highlight=edge_blend

Which lead me back to here...

http://sites.google.com/site/bagginsbill/free-stuff/orbs

Something based on Orb009 ("Pickled") perhaps?