I seem to be one of those unusual people that have never ventured into the world of CPA, despite being involved in IM/SEO for almost a decade. I have a few sites that are regularly generating 700k-900k unique visitors per month, most of which is driven by viral content that's focused on a particular subject (low carb dieting, fishing, pre-school education, pregnancy etc). We do reasonable enough money via AdSense and native advertising, but would like to explore the possibilities of including CPA offers on our sites. Simply throwing a banner ad or text link for a CPA offer isn't going to do much good. I've considered using an interstitial ad and geo-targeting the contents of it, but other than that I'm not sure how to proceed. We want to keep clear of forcibly re-directing visitors, but would be open to using pop under/over, interstitial etc. I'd really appreciate any input.