Manage your tabs in sandboxes increasing your privacy!
Run profile manager and load additional profiles in a new Firefox instance. Switch profiles and cookies of a webpage. Create, delete, edit, duplicate and backup a profile. Synchronize two profiles using Dropbox synchronization. It's also possible to synchronize ScrapBook and Zotero folders.
real time social browsing - With the SamePlace extension for Firefox, you can enter a virtual place associated with each web page you visit, and meet others who did the same. realised with jabber
another ff automation tool
Cookies when you need them, not when others need them to track you - gets rid of a site's cookies as soon as you close its tabs.