My 2^nd article on the winning pair has been published on SilverlightShow. I think, and I hope, it is quite interesting because it shows how to use the Silverlight Client Object Model and some other things. In summary what you will find is:

• query the Sharepoint object using the Silverlight Client Object model
• fill a DataGrid with the List and Libraries of a Sharepoint site
• drag & drop of one or more files from the file system into the Datagrid
• upload of one or more files in the Sharepoint List corresponding to the DataGrid row selected when those files were dragged
• another method to insert the Silverlight application in Sharepoint page
• pass parameters from the host Sharepoint web part to the Silverlight application

You can read my article here and watch this video where I create the application which performs the tasks above.

By the way, here you can download the source code.