Here is a simple example of what you can do with pixel shade effects.
Basically is a simple image on witch you apply the RippleEfect and animate it. In this example is the same effect three times.
Two are animating the water and one is applied when the surface is clicked.
To make this work you need to add a reference to the ShaderEffectLibrary.dll.
By doing so you will have 23 effects available, this is just one of them.
Here is the source code … just in case . WaterInSilverlight.rar