eisenivan

A lightweight plugin that allows you to place a sitewide alert message in the header of your site. There are options to include a default set of styles (based on Twitter Bootstrap), center your alert, and switch the style class.

Summits Alert

A lightweight plugin that allows you to place a sitewide alert message in the header of your site.

Rupok

Eity

An announcement plugin that shows your announcements/breaking news/offers/notice on top of the website. 
Stylish show of announcements will attract the eye of your visitors. Fully controlled by date. Best suitable for promotional offers, Notices etc.
Here you can get more information about this plugin – http://www.rupok.me/projects

Responsive News & Announcements

An announcement plugin that shows your announcements/breaking news/offers/notice on top of the website.

Summits Alert vs Responsive News & Announcements