Erick Hitter

Oomph, Inc.

Allows users to point WordPress objects (posts, pages, custom post types) to a URL of their choosing, which is particularly useful for injecting non-WordPress content into loops. The object appears normally in any loop output, but visitors to the object will be redirected to the specified URL. The plugin also allows you to choose the type of redirect, either temporary (302), or permanent (301).
Through a filter, the External Permalinks Redux meta box can easily be added to custom post types. There is also a function available for use with WordPress’ <code>add_meta_box</code> function.
This plugin was originally written for use on WordPress.com VIP. It is inspired by and backwards-compatible with Mark Jaquith’s Page Links To plugin, meaning users can switch between plugins without risk of losing any existing external links.
This plugin is translation-ready.

External Permalinks Redux

Allows you to point WordPress objects (posts, pages, custom post types) to a URL of your choosing.

Andrea De Giovine

External Links Mask add a Out links section in your WP ADMIN and mask all external links in post content.
Major features in External Links Mask include:
<ul>
<li>Hide external links.</li>
<li>Mask long external link.</li>
</ul>
PS: This plugin work only for post content links.

External Links Mask

External Links Mask add a Out links section in your WP ADMIN and mask all external links in post content.

External Permalinks Redux vs External Links Mask