If you aren’t aware of the Silverlight Media Framework, you should definitely take a look at this post of Tim Heuer.
You see, the SMF itself is essentially a set of controls…but not an
‘app’ itself that you can just consume the binary. What I did was
basically create a new Silverlight
application myself with one simple element: Player. This way I could
implement what I needed for my use. The first thing I wanted was to
have a simple XAP that I’d be able to load parameters in…very much like
we did for SL Video Player on codeplex. To make essentially the player
have a flexible use model. I could host the player anywhere and just
feed it media to play.