Ads EZ is personal ad server with numerous features. It centralizes your banner ads in one location, and provides a modern interface to manage them.
The 99 Robots Simple Ad Spot plugin is the easiest way to place an advertisement in your WordPress site.
OpenX WordPress Widget is a plugin for wordpress websites and provides a simple, straightforward way to place ads from a Revive (formerly OpenX) AdSer
Fun for everyone!
Uses WP "pseudo-cron" system to automatically purge OpenX statistics data.