Recs.
Updated
Saves up to 95% of memory because it reduces the number of open tabs in Google Chrome and Mozilla Firefox.
Specs
Pros
Pro Overall very useful
It takes all of your tabs (choose between all/all-except-current/current/all-to-right/all-to-left) and turns them into links in a special OneTab tab where you can further manage your tabs by dividing them into groups, removing duplicates and securing them so that they can't be removed unless unsecured.
Pro Provides just enough information
OneTab provides just the right amount of meta-info about the tabs you've saved. It groups them by session, and tells you how many tabs are in each session, as well as the date the session was created. Every saved tab includes the bookmarked favicon and page title.
Pro Non-invasive
The OneTab dashboard only appears the first time you open your browser after quitting, although you can also make it appear through the extension button in the extensions bar. This is less invasive behavior than the Chrome extensions that appear every time you open a new browser tab.