There was a lot of excitement when we wrote about the Greasemonkey script that could be used to switch between multiple Gmail accounts. At that time Thilak commented about a Firefox extension that basically accomplished the same task. With it you create user profiles that you can switch between, and it uses a different set of cookies for each of the profiles.

Since most sites store session information in cookies this is a good method for switching between multiple accounts, whether it be for email, shopping, or just about anything. That’s when it hit me that you can manipulate cookies using JavaScript as well, and I figured there had to be a way to create a bookmarklet to do almost the same thing as the extension.

Quoted: FireShot is a Firefox extension that creates screenshots of web pages. Unlike other extensions, this plugin provides a set of editing and annotation tools, which let users quickly modify captures and insert text and graphical annotations. Such functionality will be especially useful for web designers, testers and content reviewers. It's possible to choose whether entire web page or only visible part of this page should be captured. Screenshots can be saved to disk (PNG, JPEG, BMP), copied to clipboard, e-mailed and sent to external editor for further processing.

Not available for Linux.

Quoted: Tired of that boring default icon next to your bookmarks? This extension adds a interface allowing you to pick the icon for each of your bookmarks.