Sun Releases Looking Glass 3D Desktop
 

Looking Glass, which was first shown off in 2003 and released as an open-source project in 2004, allows users to run a Java-based desktop environment on top of Windows, or on Linux or Solaris. The software allows certain applications to be run in a "2.5D" environment, allowing them to be rotated in 3D space to maximize the available desktop space.

https://lg3d-core.dev.java.net/binary-builds.html