http://wordpress.org/extend/plugins/adrotate/ - AdRotate
A powerful ad manager. Counts impressions and clicks well.
http://wordpress.org/extend/plugins/search-and-replace/ - Search & Replace
A simple tool for replacing strings in your database.
Pretty handy if you want to replace a lot of sponsor links with a cloaked Pretty Link url in just a couple of seconds.
http://wordpress.org/extend/plugins/...seo-meta-tags/ - Category SEO Meta Tags
Allows you to add custom meta tags for category and tag pages. Usually All In One Seo can handle the Meta Titles of your categories but not the meta descriptions.