Join some affiliate networks like maxbounty and you can see many interesting CPA offers like IQ test and funny surveys. Humor sites are not hard to monetize, I suppose.
I agree that CPA affiliate networks may work well for you. There are a large amount listed here. There are quite a few networks that have entertainment sort of campaigns. If this doesn't work out for you then you could also try CPM ad networks. There are some good ones listed on the same site. Infact the first 2 networks listed here are very reputable. I use them on my entertainment site and earn around $.40 - $.70 CPM on each banner ad format where I use 3 different ads per page giving be around $1.20 - $2.10 CPM on banner ads alone. Good luck with your humor site.
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