MySocial 24x7 is a sidebar extension for firefox, a perfect companion for FriendFeed.
With MySocial 24x7, you can explore Everyone's, Your Friend's, and Your Feed.
You can comment and like any entry. You can also reply to an entry via twitter.
You can preview images right from the sidebar. MySocial 24x7 also supports Alerts (Windows, FFb3 on Mac with Growl).
Your passwords are stored in Firefox Password Manager.