These aren't all that can be done, but they're the ones Mage liked for his siggy :) At least they look good by themselves, a little too much all together, me thinks. ..  You may want to view them seperately by right clicking over the image and choosing the "open in new window" or "view image" option. 
 
Colors :
This one just rotates the colors, you can get some of the colors removed, but that kinda messes with the smooth flow there. It's a little too uhmm.. bright for me, personally.
This is another of my favorite effects for the stars and flares.  Just kinda a simple and muted effect =)
Gray Fade : 
Okay, now this one you'd have to watch carefully because I put it on only one animation loop. It's actually one of my favorites, something understated.  Uhmm.. it might have been better if I reversed the effect ..  if you missed it ~ just reload the page :)
Close Ups :
This isn't one of my favorites, but does the job for an "impact" impression =)