How to Create Dashboard Widget

I would like to create a plugin to show something on dashboard. I have experience with creation of normal widgets, but the dashboard widgets does not work for me. I have even try examples like http://lesterchan.net/wordpress/2008/03/19/dashboard-widget-without-controls-sample-plugin/ but they do not work (at least at the latest 2.6). Working sample would be great.

P.S.: and no, i do not want to use Dashboard Editor plugin!