OneTab - Whenever you find yourself with too many tabs, click the OneTab icon to convert all of your tabs into a list. When you need to access the tabs again, you can either restore them individually or all at once.
tabExtend - Easily save tabs and quickly create notes in your browser
Workona - A better way to work in the browser.
Toby - Better Than Bookmarks
Lightbeam for Firefox - Mozilla is the not-for-profit behind the lightning fast Firefox browser. We put people over profit to give everyone more power online.
Tabbie - The missing tab manager for Chrome