In this sample, Gill Cleeren has created a very simple DTP application (desktop publishing application) which allows the user to draw on a Canvas, add some text and some images. After that, he can print the result.
Probably the most requested feature for Silverlight 3 was being able to print or export the contents of a control so that we can save it and then print it. While there is no Print class of some sort directly available in Silverlight 3 either, we can print, using some small workaround. And that workaround goes by the name of the WriteableBitmap.