@Nigezu: If he searchs for backdrop the chances of finding anything are pretty slim. You could at least point him to "skycube" or "skybox" instead of simply ranting.
@swdison: The "backdrop" is a huge cube, called a skybox. Somewhere in your folders there are some skyboxes made of 6 individual images, one for each side of the cube.
There are some ways for changing the skybox or cube but I never used any so I'm limited to memory. Now you can look around in the forum for it.
Good luck.
I'm pretty sure I know everything. Doubts are something rare in me and I am never wrong, as this signature can prove.