Inking on Video with Silverlight

Microsoft’s Stefan Wick continues to pump out some great Tablet PC ink and Silverlight stuff, this time delivery some ink video goodness, along with a sample app and a sample for you to try on his blog. Check it out:

Silverlight makes delivering video content in the browser very easy. Silverlight also has ink support built-in. So why not combine these two features to enable some great new scenarios?

I have put together a little sample using Silverlight v1.0 to record and play back ink annotations, synchronized with the video playback.

What are some great ways that annotating / inking on web-based video could be used?