Just playing around really.
Bigger Version

Those are really kewl iridescent effects.

Thanks! Yeah I'm playing around with lighting effects lately, I'm still not quite happy with them but you can do some pretty nice things using a good gradient, bluring and transparency.

The way this guy draws background lighting effects is really amazing. He uses photoshop I think. He just designed http://www.newspond.com which got me wanting to play around with background light effects.