Not new but usefull.
There are a huge number of 3rd party tools for Flash Developers. This is a natural phenomenon when you have a successful platform with a large adoption in the marketplace. The same growth in prominent in the .NET tool space. Now that Silverlight 2 is alive and doing well we should expect to see more commercial and open source tools released that target the Silverlight developer and designer.
SWF Editors
In the Flash world you create your application and store the source in a .FLA file. The FLA file is compiled into a SWF file for deployment. There are a number of decompiler tools for SWF files. Surprisingly another set of tools has emerged – the SWF editors. These editors can open an SWF file in edit mode. Then you can modify the flash application and save the changes back into the SWF file. Some of these editors are quit powerful and enjoy a wide audience.
Turning their eyes toward Silverlight
It seems that some of these companies are beginning to take notice in Silverlight. SourceTec Software makes a number of Flash tools including their Sothink SWF Quicker editor. They have just released a beta of Sothink Quicker for Silverlight.
from Walt Ritscher more here