Did you know OS X Mountain Lion has 43 secret wallpapers? Each wallpaper is a 3200×2000 resolution, here’s how to find them:
From Finder, hit Command+Shift+G to summon Go To Folder and copy paste the folder path below.
Here you can browse the hidden wallpapers and set them as your current wallpaper if you wish. The categories of the wallpapers are as follows National Geographic, Aerial, Cosmos , and Nature Patterns. Below is a video showing off this quick tip.