It was one "few days work" demo somebody threw around when they first were able to manipulate windows in 3D in a compositor with Java, but it got traction in parts of the OSS blogosphere/forums as some revolutionary new desktop experience (even though there were already several similar commercial offerings, and itself was little more than some little-thought 3D manipulations and in no way an actual full SUN project).
It was touted as "SUN innovation" example, and predictably, it got nowhere.
E.g. there was a node.js based editor that was the talk of HN for a while. Got nowhere, was just a simple editing window + crude syntax highlighting, and it was obvious from the start that it wont go anywhere with its direction and chops, but not if you heard the gasps just because somebody powered an editor with Node:
Or the Lighttable editor -- itself being abandoned for the next shiny endeavor, which again makes sense as it was just some inline REPL touches on top of a crude editor. At least that explored the design space a little, but the promises where touting it as the next thing that will revolutionize programming...