markup-Icons:
http://www.famfamfam.com/lab/icons/silk/
Creative Commons Attribution 2.5 License. 

jquery.elastic:
http://plugins.jquery.com/project/elastic

jquery.listen:
http://plugins.jquery.com/project/Listen

bbparser:
http://www.dreamincode.net/code/snippet304.htm

textileparser:
http://jrm.cc/extras/live-textile-preview.php

markdownparser:
http://attacklab.net/showdown/

jQuery-preview-idea:
http://www.learningjquery.com/2006/11/really-simple-live-comment-preview