Eclipse is slowly moving into the direction of a Rich client platform (RCP). With SWT (Standard widget toolkit) for native UI's, JFace and and an RCP toolkit it provides a nice framework for building applications. Some examples where provided at the EclipseCon 2004.
Tried the RCP framework this weekend and again my conclusion is that the weakest point in Eclipse is Java itself. By the way there is a nice lightweight alternative to RCP called RCPLite.