MarkUp is a nice online tool that helps you quickly markup a webpage and then share it with others. It offers a browser bookmarklet that you need to click when you want to use it. You can use it to annotate webpages using various shapes like arrows, boxes circles etc. It also lets you mark specific portions on the page and then add notes.

Once you are done, you can hit the publish button on the top right panel, and it will create a public URL of the marked up page that facilitates easy sharing.

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The good thing about the URL which it generates is that the person with whom you shared the link with can quickly create his or her notes and markups on the page and then create a new URL to share it back. He doesn't need to go to MarkUp's original site and get the bookmarklet.

Features