eBay is offering website operators an additional "monetization stream" with a new keyword operating system, called AdContext.

AdSense employs a contextual system so that internet users can be directed to eBay auctions according to keywords on the webpage that they're visiting.

Site owners who use the advertising system will then get a cut of the revenue from the sale of products.

According to eBay's website, "The contextual ads take into account the popularity of certain keywords on eBay, not just the keywords on a given Web site".

"We want to increase the number of times buyers come to particular sites", says eBay's chief strategy officer, Michael van Swaaij.

Analysts say that it could be a good way for bloggers to generate revenue from their websites, although they'll only make money if visitors to their website buy products.

As eBay is one of Google's biggest advertising customers, analysts are viewing this development with interest, as the system could be expanded to rival to Google's AdSense.