eBay developer Sellebrity, has introduced a new tool called “Social Streamer” aimed at helping sellers promote their listings for free on social networks like Facebook and Twitter.

Social Streamer works by monitoring how listings change over time due to social factors, such as bids, watch counts, links, bookmarks to the listing, and questions asked. The tool compiles and analyzes this information, and in some instances, will use it to attract a buyer on a special landing page.

For example, a rare item can be promoted initially as a good deal because it has no bids. Over time, the listing can be promoted using social data, and before the auction ends, it can be promoted as a last-chance offer.

“People kept saying they did not get the Social Networking thing, so we made a tool for them,” a spokesperson for Sellebrity said.

“This new social tool comes with lots of extras: It optimizes itself using analytics, and it also engages buyers at a very personal level before they get to eBay. Social Streamer was created to help every seller, regardless of who they are or what they sell.”