Toby - Better Than Bookmarks
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.
Tabbie - The missing tab manager for Chrome
Session Buddy - Manage Your Browser Sessions
Workona - A better way to work in the browser.
xTab - Limit the maximum number of tabs you can open at once