OpenGG

Simple and small lightbox clone, Modded from Joel Vardy’s lightbox, more info at http://blog.ilooker.tk/
Download and install, that’s all you need to do. And when you post articles with images, this plugin (the js script actually) will automatically lightbox those unlinked images (would not affect those images with links).
For example, I posted an article, with two image unlinked to anything (let’s call them image1 and image2), one image linked to another webpage (called image3). Then when someone click on these three images, image1 and image2 will be lightboxed but image3 will not.
Demos: 
<a href="https://jquery-littlebox-for-wp.googlecode.com/svn/trunk/demo.htm" title="Demo on Googlecode" rel="nofollow ugc">Demo on Googlecode</a> 
<a href="http://blog.ilooker.tk/" title="My blog" rel="nofollow ugc">My blog</a>
<h3>Issue list</h3>
<ul>
<li>Large image overflowing issue;</li>
<li>Iframes and flash objects unsupported yet;</li>
<li>Image groups unsupported yet (one click one image, no prev/next);</li>
<li>Not so customizable for users yet;</li>
<li>UI design improving needed.</li>
</ul>

jQuery Littlebox for WP

Simple and small lightbox clone, Modded from Joel Vardy's lightbox, more info at http://blog.ilooker.tk/

Kevin Newman

WraithKenny

This plugin allows Admin users the ability to add custom CSS and JavaScript directly into individual Post, Pages or any other registered custom post types. You can also add classes to the body tag and the post container. There is a Global settings page for which you can write Scripts n Styles for the entire blog.
Admin’s can also add classes to the TinyMCE “Formats” dropdown which users can use to style posts and pages directly. As of Scripts n Styles 3+ styles are reflected in the post editor.
Because only well trusted users should ever be allowed to insert JavaScript directly into the pages of your site, this plugin restricts usage to admin type users. Admin’s have access to even more sensitive areas by definition, so that should be relatively safe 😉
<h4>Notes about the implementation:</h4>
<ul>
<li>Admin users, or more specifically, any user with the <code>manage_options</code> and <code>unfiltered_html</code> capabilities (which by default is only the admin type user) can use this plugin’s functionality. Some plugins extend user rolls, and so this plugin would naturally extend include rolls that have the appropriate capability.</li>
<li>CSS Styles are embeded, not linked, at the bottom of the <code>head</code> element with <code>style</code> tags by using <code>wp-head</code>. If your theme doesn’t have this hook, this plugin (as well as most others) won’t work.</li>
<li>JavaScript is embeded, not linked, at the bottom of the <code>body</code> (or <code>head</code>) element with <code>script</code> tags by using <code>wp-footer</code> (or <code>wp-head</code>). If your theme doesn’t have this hook, this plugin (as well as most others) won’t work.</li>
<li>There is no input validation. This plugin puts exactly what you type in the meta box directly into the <code>html</code> with no error checking. You are an Admin, and we trust you to be carefull. Try not to break anything.</li>
<li>Do to the licensing of the libraries used, this plugin is released “GPL 3.0 or later” if you care about those things.</li>
</ul>

Scripts n Styles

This plugin is simply awesome. 
No other words to say. 

Must have! Great Job.

This plugin allows Admin users to individually add HTML, custom CSS, Classes and JavaScript directly to Post, Pages or any other custom post types.

jQuery Littlebox for WP vs Scripts n Styles