CodeAndReload

This plugin provides the ability to have randomly selected quotes displayed on the admin page, by using a 
shortcode or by using a sidebar widget. The quotes include user-entered quotes, and can optionally include 
excerpts from a user-chosen category and can also optionally include links from a user-chosen links category 
There also is an option for including the lyrics from “Hello Dolly”. The plugin can be used for random 
quotes, rotating testimonials, rotating random affiliate links, or random featured posts. It was inspired by 
the Hello Dolly plugin (hello.php) that comes bundled with WordPress.
<h3>Support</h3>
Technical support for this plugin will be provided via the WordPress plugin forum. Additional support may be 
available at <a href="http://www.codeandreload.com/wp-plugins/nicequotes/" title="Nice Quotes at Code
and Reload">plugin’s homepage</a>.

Nice Quotes Rotator

Allows display of random quotes via shortcode, a sidebar widget, and/or on the admin page. Quotes can be user-entered, post excerpts or links.

jwmcgregor

You know you need to blog, sometimes it can be a challenge and sometimes it is hard not to focus on the long term goal This is where Hello Motivtion will help, displaying random motivational quotes on the top right hand side of your wordpress screen while you are working in your blog. This plugin is based on the Hello_Dolly plugin by Matt Mullenweg

Hello Motivation

A little plugin that will motivate you while your working in wordpress.

Nice Quotes Rotator vs Hello Motivation