You have three ways to play streaming media in a Web page. You can specify a URL in the control, such as a local .wmv file on your computer, or specify a URL dynamically through a client-side function (which, again, could be a local .wmv file on your computer), or you can specify a media source through a Silverlight Streaming account. These methods are discussed in the section Dynamically Playing a Media File of Using the Windows Live Tools Controls.