Here are the few links i found on the web for CodeIgniter tutorial/sample application:
http://video.derekallard.com/
http://godbit.com/article/introduction-to-code-igniter
http://www.mrforbes.com/wordpress/2007/05/13/a-quick-code-igniter-and-query-ajax-tutorial/
http://www.maestric.com/wiki/doku.php?id=php:codeigniter_template
http://68kb.com/2007/10/28/templating-with-codeigniter/
http://swik.net/codeigniter+Tutorial
http://www.michaelwales.com/2007/09/live-tutorial-codeigniter-blog/
http://mini-app.peccavi.com/page/docs
http://www.jimohalloran.com/2007/09/23/building-a-complete-codeigniterapplication-part-2/
http://pr0digy.com/category/mootools/
http://pr0digy.com/archives/
http://www.alexajax.com/
http://bleakview.orgfree.com/obsession/
http://www.4webby.com/freakauth/tutorials/using-zend-framework-omponents-in-code-igniter
http://www.4webby.com/freakauth/tutorials/ci-swift-mailer
http://www.ngcoders.com/php/pquery-for-code-igniter-v-15x/
http://www.glossopteris.com/journal/post/table-relationships-in-ci
http://simplepie.org/
http://www.phpinsider.com/php/code/ContentFeeder/
http://www.ciforge.com/CodeIgniter_ApiDocs_1.4.1/