Silverlight XAML Primer 4, Listing 2
Creating vertical oriented gradient colors by changing the LinearGradientBrush's StartPoint and EndPoint attribute values
<Canvas xmlns="http://schemas.microsoft.com/client/2007">
<Rectangle Width="500" Height="500">
<Rectangle.Fill>
<LinearGradientBrush StartPoint="0,1" EndPoint="1,1">
<GradientStop Color="Purple" Offset="0.0" />
<GradientStop Color="Red" Offset="0.25" />
<GradientStop Color="Navy" Offset="0.50"/>
<GradientStop Color="Yellow" Offset="0.75" />
<GradientStop Color="Green" Offset="1.0" />
</LinearGradientBrush>
</Rectangle.Fill>
</Rectangle>
</Canvas>