Experiments are underway to re-implement the interface in Unity 3D. The goal of the new version will be to make the 3D interface accessible and navigable within standard browsers without special plugins. Here is a video of one of the experiments.
The above examples are just the latest generation of Dr. Mary Hopper’s experiments with creating 3D interfaces to traditional, interactive and 3D content. The first generation of experiments were in Apple’s HyperCard back in the 1980s. Much more about the history of the 3D interfaces and the new experiments will be posted soon, so please stay tuned!
In the meantime, here is a page with a longer history of the project: Knowledge Places History