Gradients, Blending Modes and Adjustments

So I was messing around on Photoshop while creating my portfolio, which is gonna be awesome btw, and I stumbled upon an interesting technique. Try figure out how I pulled it off:

Any idea?
If you thought the title of this post, you're right!

I have this technique where I use about 3 levels of Threshold to create a comic effect (as per my tutorial on Digital Bubble) and some sort of drawn style. During Experimental Week, I realized that the same can be achieved using Posterize set to 3 levels, a Curves adjustment to control the sizes of the levels, and a Hue/Sat to remove the color :-S
Just like in my Just Remember post... lol

Anyway, I wondered "What else can Posterize do?"
Well, quite a bit more. Coupled with the Gradient tool, some layers and Blending Mode play, and as always a Gradient Map to top it all off, it created the "circular" and "shapes & colors" designs. (I actually used the same Gradient for the map (laziness))

Drop by soon for more info on how I pulled this off, though I'm quite sure you already know how it was done...

Also, I gained a liking for Trebuchet! It's lovely!!

Cheers!!