Would it be possible to make a pluggin for Thickbox so that the few code bits needed to reference it would be all that people would need to add to their links?
You can read a little more about it here and see examples: http://jquery.com/demo/thickbox/
It degrades nicely. If Javascript is off, it just opens the linked file or website in a new window. If it is turned on...you have to put class="thickbox" into your link and make the title tag reflect what you would want in a caption or title. Voila! There are some more complex bits of code to do in the title tag if you want to do iFrames and such...
I don't know how hard it is to make plugins for Moodle, or if there are any drawbacks to using this automatically on a Moodle site.
Here's an actual example of how I code it now in the book module for a French course and I have attached the files for you if you want to try it out. I had to make one change to the CSS file so that it didn't conflict with Moodle.
Cheers,
Ian
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<!--note, the next three script links allow the image enlargement to work on this page-->
<link rel="stylesheet" href="http://cll-devel19.lms.athabascau.ca/file.php/30/javascripts/thickbox.css" type="text/css" media="all" />
<script type="text/javascript" src="http://cll-devel19.lms.athabascau.ca/file.php/30/javascripts/jquery-latest.js"></script>
<script type="text/javascript" src="http://cll-devel19.lms.athabascau.ca/file.php/30/javascripts/thickbox.js"></script>
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<div style="width: 250px; float: right; margin: 40px 0 0 15px; color: #666;">
<a href="http://cll-devel19.lms.athabascau.ca/file.php/30/images/illustr/mod04_lec11_louis14.jpg" title="Portrait of Louis XIV, Hyacinthe Rigaud, 1701, Louvre, Paris." class="thickbox" >
<img src="http://cll-devel19.lms.athabascau.ca/file.php/30/images/illustr/mod04_lec11_louis14_sm.jpg" alt="Louis XIV" width="250" height="355" border="0" />
</a>
<p><em>Portrait of Louis XIV</em>, Hyacinthe Rigaud, 1701, Louvre, Paris. Image: <a href="http://commons.wikimedia.org/wiki/File:Louis_XIV_of_France.jpg" target="_blank">Wikimedia Commons</a></p>
</div>
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