Using a standard WordPress (2.5+) installation, the la petite url WP plugin allows the user to create shortened, unique, permalinks to their content using a combination of lowercase, uppercase, and numeric characters, which originate from their own domain name. By default la petite url generates a 5-character combination of lowercase letters only, for ease of use in entering on a mobile device or handset. Which URL would you rather explain to a friend or new acquaintance in person?
http://extrafuture.com/2009/04/08/on-url-shortening/
or
http://extrafuture.com/msfxe