Network extensible Window System
(NeWS) An elegant PostScript-based windowing environment, invented by James Gosling, the author of GOSMACS.
NeWS would almost certainly have won the standards war with the X Window System if it hadn't been proprietary to Sun Microsystems. There is a lesson here that too many software vendors haven't yet heeded. Communication is based on PostScript and server functions can be extended.
See also HyperNeWS, OpenWindows.