CMS Tree Page View plugin by Pär Thernström adds a CMS-like tree overview of all your pages to WordPress – like the view often found in a page-focused CMS. Within this page tree you can edit pages, view pages, add pages, search pages, and drag and drop pages to rearrange the order.
See all pages – including private and drafts – or just publicly available pages
drag and drop to rearrange your pages
add pages after or inside a page
This plugin looks very good to manage pages effectively for sites, with many pages.
Plugin homepage, download and features video at: http://eskapism.se/code-playground/cms-tree-page-view/