I am looking for a library to create custom shaped windows in mac which I will use to create a tool similar to a Yahoo Widget. The solution should be able to take a JFrame instance (and if necessary an image describing which regions to be transparent) The solution can _NOT_ be a robot instance taking a screenshot or any similar low quality/low end solution. It has to feel or be system native. Commercial libraries are OK as long as I know about their pricing ahead of time and they are affordable and don't have reoccuring costs. Ideally the solution would also allow me to do shaped windows on MS windows. The programming platform is Java, there probably will be OS dependent code which should work on Mac, and if possible also Windows and Linux.