Here's another list...Haven't tried them, but if you have please leave a comment:

* Clicksor (http://www.clicksor.com/)
* TargetPoint (http://publisher.targetpoint.com/)
* Adbrite (http://adbrite.com/)
* BidClix (http://www.bidclix.com/)
* Chitika (http://chitika.com/)
* AllFeeds (http://www.allfeeds.com/)
* Adhearus (http://www.adhearus.org/)
* AffiliateSensor (http://www.affiliatesensor.com/)
* Bidvertiser (http://www.bidvertiser.com/)
* Veoda (http://advertise.veoda.com/)
* Kanoodle (http://www.kanoodle.com/)
* Enhance Interactive (http://www.enhance.com/)
* Quigo (http://www.quigo.com/)