1. +Photo Zoom
+Photo Zoom is a simple extension providing fast and simple zooming for photos within your Google+ Stream.

2. Google+ Notification Checker
Displays the number of unread notifications in Google+. You can also click the button or the notification to open Google+ homepage.

3. Google + Tweet
Google+Tweet  integrates a full featured twitter client inside your Google Plus Account!

4. Replies and more for Google+
 Reply and Reply to Author links for easy +mentions of other users
 Badges the favicon with a number when you have new messages
 Ctrl+Enter and Shift+Enter submit a comment or post
  “M” key mutes a post
  Header bar floats down as you scroll
  Adds a dropdown next to share with additional sharing options (Twitter/Facebook/Email)

5.Google+Facebook
Google+Facebook allows you to see your Facebook stream inside Google+.

6. GPlus+ Search
Social Search , Makes Searching Your Stream Easy

7.Beautify G+
 Fixed position of the menubar
 Fixed position of the left column
 Fixed position of the right column
 +1 any Website you are on
Option to hide suggestions and “Go Mobile”
Option to enable favicon notifications
 Option to enable audio notifications

8.+Comment Toggle
+Comment Toggle hides any comments to posts within your Stream and makes them available if and when you actually want to see them.

9. Surplus
Post or respond from within the popup
Desktop Notifications
Notification sounds
Switch between multiple Google accounts

10.Extended Share for Google Plus
Google+ does not have a quick way sharing your posts to Twitter, LinkedIn, Facebook, and Tumblr this extension will add a link “Share on …” to each post. Once clicked, it will bring up an internal bubble asking you where to share your post.