Rather than paying on a per click basis, these ad networks pay on a per view basis (usually a dollar amount based on 1000 pageviews).  Most of these networks require that you have a large visitor base to be approved to their network; therefore most of these won’t work for a smaller niche sites.

1. ValueClick Media

2. Tribal Fusion (500,000 unique visitors per month required).

3. Adbrite (update – Adbrite is shutting its doors on Feb. 1st 2013).

4. Casale Media

5. ePom.com

6. Adblade.com

7. Advertising.com (part of AOL)

8. Burst Media (25,000 monthly page views)

9. CPX Interactive

10. Technorati Media

There are a TON more CPM ad networks out there, this is just a small sample.  You need to find one that fits your niche or works best for your site