John Kolbert of Techlyzer has produced a great screencast explaining how to create the collapsible and movable option boxes within the WordPress 2.7 write new page/post screens. The tutorial starts off by creating a dummy plugin which you then add functions to which give it the draggable/collapsible options within the Administration panel. John provides a sample plugin to use as well as a link to the article on the Codex that explains the add_meta_box function.
This tutorial is mainly for those aspiring plugin authors as well as for those who would like to add this type of functionality to their own plugin. John should rename this video to add_meta_boxes explained in plain English because even I understood and learned a thing or two. Final though is that I would absolutely love to see more screencasts like these in the future and have them embedded into their respective Codex articles. How cool would that be?