yolkworm a short and sweet tut:

1.Go out to the road pick up one dead Green Iguana (road kill).

2.Slap him/her down back first on to scanner.
(if you don't have the real thing find a Iguana image)

3.Scan Iguana (then clean all that strange goo off glass).

4.Make small interesting selections from the scanned or found image in many little areas and then copy them to a new canvas: copy > paste > and distort, copy > paste > and rotate, copy > paste > and re-scale a little, etc.

5.Keep cloning interesting areas then copy > paste > and distort or rotate till you fill the canvas, then using your smudge and blur tools clean up all the imperfections.