Openads (formerly known as PHPAdsNew) is now rebranded as OpenX. This project started a few years back to provide an open source Advertisement Management system. Currently, it is one of the most extensive OSS Ad management system out there, with tons of features.

This year OpenX plans to bring out a hosted version of OpenX allowing more publishers to leverage the use of this platform, without having to install and set it up on their own servers.

Read more : http://blog.openx.org/02/changes-to-openx-site-and-brand-quick-guide/