Nice Wallpaper Sites

I started looking for Mac Wallpapers, then got sidetracked on “Windows 7” (codename for new Windows version that will follow Vista) and wallpapers for it, and then found these sites which have some nice Mac wallpapers:
http://www.hongkiat.com/blog/60-most-beautiful-apple-mac-os-x-leopard-wallpapers/

I also saw on the same site so Dual Screen wallpapers, which are pretty nice too:

And here’s another dual screen wallpaper site:

Enjoy!