I just got an email from Ben Williams and he mentioned the Add Silverlight to SharePoint 2007 article on LiveSide where you create a custom JS file, create a custom web part (code it up) and BAM! Silverlight in SharePoint).

Another option for this (if the content is public I.e. can use security through obscurity)  which doesn't require development is to use Silverlight Streaming and just IFrame in the content.

Here are directions:

  • get the content into Silverlight Streaming by Windows Live (see http://dev.live.com/silverlight for more information)
  • add a Content Editor Web Part to the SharePoint site
    • Set the source of the content Editor Web Part (in the browser)  to contain an IFrame

<iframe src=http://silverlight.services.live.com/invoke/6579/WLTVSEMEAREHEARSAL/iframe.html" frameborder="0" />

  • View the page and the iframe will instantiate a Silverlight application inline.