The concept behind CGSphere is great: You go to the site, download the Sphere scene to use in any 3D rendering program (if you do not have a 3D rendering program, might I suggest Blender?), and manipulate the sphere into whatever your imagination can conceive. The only limitations are that the dimensions of the sphere must remain somewhat the same, and you can't change the camera angle. Other than that- the sky is the limit. When you finish, you can upload your picture back to the website, where other participants can rate and comment. The results, which can be seen in the gallery are amazing.

CGSphere is such a simple idea and offer two exciting possibilities. The first, and most obvious, is that if your students are working in 3D modeling, they can participate in the project. The second, is that this is a great idea for a lesson in any medium. The students can create a composition with one rule: it has to have a sphere in the center.
Or a box.
Or a tube.
Or a pyramid.
Or whatever.

The thing that I found most fascinating about projects like this is that the resistance to uniformity imposed by these limitations is the driving force behind the creativity of the participants.