WP Socializer is an advanced plugin for inserting all kinds of Social bookmarking & sharing buttons. It has super cool features to insert the buttons into posts, sidebar. It also has Floating sharebar.
Advanced Post Navigator adds awesome “Next and Previous” buttons to all posts and pages. It also displays complete information about the next and previous post in a hover bubble.
Announcer is a easy plugin to add atrractive announcements, notifications, greetings, events, notes etc with attractive styles and themes.
Super RSS Reader is jQuery based RSS reader widget, which displays the RSS feeds in the widget in an attractive way. It uses the jQuery easy ticker plugin to add a news ticker like effect to the RSS feeds. Multiple RSS feeds can be added for a single widget and they get seperated in tabs
WP Selected Text Sharer is a plugin, which allows to share or search the selected texts / words of yout site. A small popup is displayed above the selected text which contains links to share / search selected text