Basic extension for Chrome which lets you add "comment" or "note" for yourself to page. Badge will show number of comments/notes.
Idea behind this is that sometimes you would like to remember some things when on page. For example you go to Amazon and it propose you change of currency (if you are buying things from different country), and you remember from your previouse visits that exchange rate isn't too great. In such case you put comment to page or domain and next time you visit it you will see comment (after clicking on icon).