Yesterday I read an article about the sourceforge project, called "Thinlet", and decided to implement a small example application.
Thinlet is a GUI toolkit, which parses the hierarchy and properties of a GUI, defined in an XML file. In this way Thinlet seperates representation, which is defined by XML, and business logic, implemented with Java. I think it can't compete against Swing, but it's a nice and easy way to create prototypes.
I implemented a small db4o browser, which enables you to browser a set of example objects. Furthermore you can delete and insert new objects into the database. To create a new file, just open any file ( *.yap) and insert objects. My Example is available through blogtorrent and my download site.