Project Description
Images are organized in a 3D space. Not 3d library is used. It doesn't use Perspective 3D which means it can perform very well.
(Perspective 3D actually take up you are lot of CPU resources)
You may further custom this project for your needs.

View in action:
3D Image Space
More Information
You can read
Terence Tsang blog about the project and how it started.
Original Blog Post:
Flash vs Silverlight: 3D Image Space