wp-imageresize

Create a menu using the featured image of a page.

Ninja Galleries lets you easily create image galleries by tagging your images and then assigning those tags to a gallery page.

Automatically watermark images as they are viewed

WP Picture Calendar shows a simple image calendar of World Days whith short description on Your sidebar.

This plugin adds a column with post's featured image before the title column on wp-admin posts list.

Prevents NextGen Gallery scripts and style from loading in to header. Useful if you don't want to use the NextGen Widgets.