On August 1st Google announced a new component of their Adwords – Remarketing.
Remarketing lets you show ads to users who’ve previously visited your website as they browse the Web.
Google has many affilate networks (ads on blogs, youtube ads, mobile ads, etc) which viewers will see after initially searching for something.
Google says that using remarketing will increase your ROI and will help deliver conversions:
Remarketing is a powerful way to stay engaged with your target audience. Presenting them with highly relevant ads and offers across the Web — and making sure your brand is top of mind when they’re ready to buy –- can radically improve ROI