Another vote for
Madison Avenue it's a pretty sweet system Marc has over there.
It auto rotates your ads and figures out which ones are making you the most money per impression.
You don't have to use their network ads either, you can use your own normal affiliate campaigns, enter your revenue numbers into the system, and it can factor that in.
It's a little bit overwhelming at first, but Marc has a guy that can set it all up for you, and I have to say, he's awesome. Anytime I have a request, he's on it instantly.
Definitely recommended.
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