I noticed that another blogger has decided to create an APEX application to collate all APEX specific jQuery plugins. I am big fan of using jQuery to extend APEX, so I hope that this idea takes off and we can all benefit.

http://lgcarrier.blogspot.com/2009/07/jquery-plugins-for-oracle-apex.html
http://apex.oracle.com/pls/otn/f?p=38200:1:0