Marcus Downing

Adds an “Identifier” column to the All Posts and All Pages admin panels, and to any custom post types. 
This column goes just after the Title column and shows each page’s slug, indented if necessary.

Page Identifier Column

Adds an "Identifier" column showing a post of page's slug, just after the Title column.

Aaron Butacov

This simple plugin allows you to use the tab-key inside the post editor to indent code or paragraphs.
This plugin should work with all versions of WordPress, but has not been tested in versions earlier than 2.9
<ul>
<li>Allows for both multi-line and single line indenting</li>
<li>Works in all major browsers.</li>
<li>Toggle-able on each post. Enable or disable tabs automatically without reloading the page.</li>
<li>Only works in the HTML editor</li>
</ul>

Tabs in Post Editor

Write code in the WP post editor? Hate not being able to use [tab]s? Now you can.

Page Identifier Column vs Tabs in Post Editor