Jared Harbour

Ever want to change the url used to display your posts? This plugin 
allows a blog administrator to change a users url slug from their edit profile page.
The plugin allows for the creation of new author slugs, but also saves old slugs a user has used in the past.

Plugin Name:       Modify Author URL

Allows administrators to modify a users author url from their profile page.

dainius.kaupaitis

When creating new post (or page) the permalink is generated automatically from title. This plugin removes „leftover“ characters (such as <code>„¢¥§</code>) from created permalink. 
NB: if you edit permalink manualy the plugin does nothing – permalink will be processed with standard WordPress procedures.

Plugin Name: Modify Author URL vs DKA More clean permalinks