I especially love the light grey back with the delicate mottling. They look just like lichen on branches. You can't really see it in my pictures.
I have one that is almost white on his back. I kept rejecting him because he was so pale when I was at the importers but the importer kept saying he was really good so I took him with some reservations. The importer was right--he is just a really light light grey. Really pretty animal. I'll try to get a picture of him. I haven't wanted to bother them. This guy in the photos above was interested enougth in the female in the cage that he pretty much ignored my phone so I got some pictures.