Enquiry and Contact form lets you create and embed standard or ajax powered forms.
Link Love is a WordPress plugin which turns off nofollow for all commenters who have posted at least 10 comments (configurable).
Better Stats Insertion is a WordPress plugin that allows you to easily insert stats code from trackers such as Google Analytics, SiteMeter, or just about any other.
FeedBuilder24 generates a custom RSS-2.0 feed from your WordPress weblog postings.
Photon is a plugin that allows to integrate phpwebgallery WordPress.
Admin Theme Preview allows you to preview of any currently installed theme without making it viewable to site visitors.
AdKit24 lets you create your own adbar for your WordPress blog.
I’ve been waiting for a new theme preview plugin for awhile, since the few I’ve had never seem to work without errors diseasing the site.
Definitely going to try out Admin Theme Preview.
Just so you all know–I made a pretty significant typo in the instructions for Better Stats Insertion. I updated the plugin, and you can grab the new, correct one here