I never can resist a nestful of baby birds. Robins build a nest on our front door wreath every spring, and then we find ourselves not using that door so we won't disturb them.
Here I was trying for a colored pencil effect.
First I kicked up the hue/saturation, also the contrast
Ran the sketcher action on one layer, then color range, highlights, delete, and set that layer to multiply
The next layer down, I used Impressionist BSOB and set it to screen
Next layer, Impressionist fine scribbles and set to lighten
Then two bottom layers seemed to be needed for depth, one set to normal, the other to multiply.
Finally I added some color and white highlights with a paint brush and added a texture.
It looks a little better full size here in my PBase gallery:
http://www.pbase.com/image/37605598