A.nnotate is the newest addition to The Best Applications For Annotating Websites. You can read more at that list about why I feel a tool like this is so critical while working with students — I’m still amazed that there are so few easy-to-use web applications out there that let you easily make these kinds of virtual “post-it” notes.
Instead of describing A.nnotate in detail here, though, I’m going to suggest you read a very thorough description of it — with screenshots — at The Make Use Of blog.
Thanks for sharing the link to a.nnotate. My students never seem to understand how to create an annotated bibliography, but this site should make that process very easy to explain and demonstrate.