Tabs Outliner - Next Generation Session, Windows, Tabs Manager and a TooManyTabs Solution That Really Works.
SplitUp! - A fun and elegant tab manager
Tab Session Manager - Save and restore the state of windows and tabs.
Tab Stash - Tab Stash is a browser extension that helps you keep your tabs straight, saved, and restore them later.
Session Buddy - Manage Your Browser Sessions
tabXpert - Next generation session manager