Michael Crump noticed a lot of confusion around flashing text in
Silverlight 4 and decided to show you a simple way to pull it off using
Blend 4.
Source: A .NET Developer's Blog
I’ve seen plenty of examples of people using code-behind to accomplish this, but this should really be handled in the View or the .XAML file (if you are not familiar using the term View from the MVVM pattern). If you can get a grasp of Storyboard’s and Behaviors, you can do a lot of things similar to this without cluttering your code-behind files.