Kishores

This is a WordPress plugin which helps in adding 
an option to your posts to enable display of more than one author-name on a post on WordPress.
<a href="http://opentuteplus.com/wordpress-post-contributors/" rel="nofollow ugc">Demo:</a>
TODO : Ajax filter for showing author on dashboard.
<h3>Arbitrary section</h3>

WordPress Post Contributors

Add an option to your posts to enable display of more than one author-name on a post on WordPress.

yonisink

yContributors creates a one-step author or contributors archive page that enables you to show any number of recent posts by each author, along with profile information pulled from each user’s wordpress user profile. This plugin shows all your members, either in table or descending form, with a jQuery searchable autocomplete-style (type and find) way to get to members. Options include excluding certain members, showing latest posts and author statistics. Also, works with User Photos Plugin (unrelated to this) to display profile photos.
For more information visit http://social-ink.net or http://www.social-ink.net/blog/ycontributors-wordpress-plugin-for-author-archives-and-contributor-index-with-photos-and-excerpts
Please note, as with every plugin or theme modification, you should do a backup of your files beforehand. Although we’ve tested this across many installs, we are not responsible for anything it does to your system and do not guarantee support.

yContributors

yContributors easily creates pretty, jQuery-searchable contributor/author indices and author and contributor archives.

WordPress Post Contributors vs yContributors