This plugin allows you to tag other registered users on your blog in a comment in order to bring them into a conversation they might otherwise be missing.

Plugin sends notifications by email after successful and failed login actions with detailed information about the user and his location.

Slide-in Notification Bar, Targeted Adverts, Ajax Based Online Counter, Most Viewed Posts, Most Viewed Categories, 4 Unique Widget

Push notification wordpress allows administrator to show simple notifications to specific users or to all users on their site.

Notification System plugin creates and maintains a notification system for users on WordPress site.