Allen Holub has an interesting four part series in Java Toolbox at www.javaworld.com. The last part presents a UI that tailors itself to the size constraints. Seems like this could be extended to tailoring to device context. Mr. Holub's approach to integrated UI with objects departs from the MVC model, but his argument for this is well reasoned. This may an interesting mechanism for handling the UI question for Jini. The articles can be found at www.holub.com also.