I am using a FanPanel as the ItemsPanelTemplate of a ListBox. The panel is infinitely scrolling when you reach the end of the listitems collection. What I mean by that is, when you reach the end of the list, if you continue to use the mouse wheel, you then have to go the other direction the same number of mouse wheel spins before the ScrollViewer will activate. This does not happen when I use a StackPanel or even a ZapPanel.
I can provide a sample solutions via e-mail if necessary.