A metabox with all page edit (and any other hierarchal post types) that display an edit link to its siblings.
Ever had to manage a WP install with many pages and subpages? This plugin does nothing more than adding a metabox to every post type that is hierarchical (that is pages and any other custom post type!) with a list of all page siblings, starting with the parent, so you can have:
News |— History |— Our Staff |—— Employment Opportunities |— Our Company
Bonus: when you're listing posts on admin pages, you can also choose to display only parents.