This email was created by [your name] who thought you would be interested in the following Article:
"Silverlight: Creating a simple smooth reverse storyboard animation on mouse enter and leave"
I have seen this question come up a lot and did not come accross a simple answer. Perhaps I just wasn't looking hard enough!
CodeProject also contains hundreds of articles, free source code samples and applications to help in your day to day programming. Why not give it a try!