I guess I didn't call it an obsession without reason, as I can't seem to keep away from those hyponotizing gradient animations. I modified the tool I posted last month so that it would output the XAML, such that a designer could actually use the tool and never touch a line of XAML. I set up the tool to output either WPF or WPF/E XAML, as WPF/E doesn't support everything (yet) that the tool uses, such as AccelerationRatio, as well as having a different namespace.
I ran into some problems with XAMLWriter and the way it strips x:Name from the XAML it produces, so there is some hacky string replace code in there that I'm not proud of. I could have used property paths as an alternative.
Because you can't use XAMLWriter in an XBAP, I made the tool a ClickOnce .application that doesn't get installed on your machine but just runs in the ClickOnce cache. Hopefully, we'll see more and more of these types of apps -- mini applications that never get installed but can do more than in-browser applications.
Download the source or run the tool. Also, check out some of the gradient animations I made with the tool and put into a WPF/E page here (screenshot below, although it doesn't do justice to the hypnotizing effect...)