Smart Notebook Express is an online alternative to installing the full version of Notebook 11 (the latest version as of September, 2012). It’s also a great backup in the event that Notebook 11 is note behaving, just as you are about to begin your lesson! The Express version allows you to create new notebooks, as well as open existing ones.
If you don’t have regular Internet access, you can even download Notebook Express Software, which allows you access to the software without relying on access to the web.
While Express lacks many of the bells and whistles of the full version, it does allow you enough functionality and access to basic tools to interact with the whiteboard.