Adsense Publishers can now expand their limits in earning money. They can earn not just by publishing contextual ads but also by referring to the products such as Firefox Broswer, AdWords and Adsense.

Recently, Google added two new products to their referral programs, the Picasa Software and Google Pack.

You’ll earn up to $2 for each time a user installs Pack and up to $1 for each Picasa install. Although Picasa referrals will be available for several AdSense languages, Pack referrals are currently only offered in US English. (link)

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