Check this out: Sam George (Principal Dev Lead @ Microsoft) demonstrates how to implement web based Ink scenarios with Silverlight.
Imagine if your users could add handwritten annotations over online photos, greeting cards or video (including live playback of your handwriting). Learn how to use Ink to take your Web sites to new heights of interactivity, personalization, social interaction, and usability. Learn the key design principles for Ink, and see how to code for Ink in the browser and on the server.
Here’s the URL for the streaming video: