Recently Safari had some unresolvable beach ball issues on my mac, so I went back to Firefox. Besides some standard extensions and add ons here are my 2 favourites for now:
Perfect organizer tool for tabs. It lets you collapse/expand all open tabs into sub trees. !! You will get addicted to it and its not available on any other browser..
A perfect tool for bookmarking/sharing articles and sites to the different channels. Besides sharing to twitter, facebook or tumblr (and more) by choosing manually the channel, i really like these services:
Pocket (formerly Read it Later) great offline reading modus. (Berlin subway “o2 can’t do” data transfer..) also very useful on Tweetbot OSX.
Buffer is a nice way to share links throughout the day. sharing means caring.
App.net I just started using it, lets see what will happen over there.