The current Flash player is primarily used to display Flash content that was initially created for the web. Screenweaver is an extension to the Flash player that aims at providing Flash developers with a toolset to produce rich media desktop applications. By doing so it enables the developer to apply their existing skill set to new uses of Flash technology.
Screenweaver enables the Flash MX, C++, VB, Delphi or C# programmer to create Win32 desktop applications that utilize Flash content as interface.
Now beta 3 is available for download which is fully functional except that it will expire on December 7th. Visit their website for more details