It looks like Google Adsense are now using a referral affiliate type program whereby if you refer an advertiser that spends at least $20 to Adwords or a publisher that earns $75 with Adsense that you earn a commission ($20). They describe the program as follows:
‘The Google referral program is designed to help businesses make money by referring small to medium-sized businesses to Google. You simply apply and once you’re approved, place links (or graphics) on your site, and then every time you refer a company that spends at least $20 with Google AdWords or earns $75 with AdSense, you earn a commission.’
They say in their FAQ that they are currently only accepting US bases sites in this program (doh!).
This program will probably suit sites that have an audience of readers who have websites that are commercial in nature.
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