Tabs Outliner - Next Generation Session, Windows, Tabs Manager and a TooManyTabs Solution That Really Works.
Workona - A better way to work in the browser.
Tab Utilities - Tab Utilities is an ultimate tab solution for all kind of users who want to manage their tab, create multiple session and search for new tabs, etc.
Session Buddy - Manage Your Browser Sessions
Undo Closed Tabs Button - Add a toolbar button onto any toolbar to undo closed tabs
Toby - Better Than Bookmarks