Awesome Screenshot is really an awesome firefox addon which allows you to capture any part of a webpage and annotate it with lines, circles, arrows, text etc. It is very handy for people who like to write tutorials. It can also be used to capture images for your personal use from a webpage in case right click is disabled on the web page. It is an all in one solution and it even allows you to blur portions of the image you have captured to hide sensitive information. And in addition to that it also allows you to automatically upto the screenshot from the same page to share with your friends, relatives etc. You can permanently store the image if you have a diigo.com account. And if you do not have a diigo account then you can save it temporarily to Awesomescreenshot.com which is removed after a month or so. This is the best screenshot plugin ever and is a must download especially for webmasters and writers.
You can download the Firefox addon from the official download page at:
https://addons.mozilla.org/en-US/firefox/addon/awesome-screenshot-capture-/