I have been toying around with JavaFX, Sun's answer to Adobe AIR and Microsoft Silverlight.  Since JavaFX is pretty much an easy way to do Swing, you can get Swing's pluggable look and feel in Java FX programs.  Thank Christ, because the Swing UI components look like shit:

demo-swing.png
Versus the GTK look and feel:

demo-gtk.png
This was done by adding the following snippet to my JavaFX code:


import javax.swing.UIManager;
 
 UIManager.setLookAndFeel(
            UIManager.getSystemLookAndFeelClassName());

Oh neat, native UI components.