After looking into managed code -> javascript and vice versa, I ran across this blog post by Wilco Bauwer: “Silverlight interoperability”
He starts it out with:
“How is any of this useful to me? I’m already using HTML/CSS/JS on the client, and I don’t have any intentions to visually enhance or replace my website.”
(On a side note Wilco has a Silverlight upload control worth checking out)