Entrecard is free Blog Advertising Network, It helps bloggers promote their blogs at the same time increase traffic. Members are required to create a 125×125 button and install a widget to their blog. To Earn EC or Entrecard Credit members must visit a blog and click the “drop” button on the entrecard widget. With EC you can advertize your blog on other blogs. The EC also serves as Entrecard currency whereby a member can trade EC for services.

Entrecard was  acquired from Graham Langdon by ZipRunner in July 2009.

From Entrecard Website

Entrecard is a free social advertising network for bloggers. The core of our business is to help bloggers increase traffic to their blogs and network with other bloggers. We help bloggers achieve this by providing users with 3 unique services: Social Networking platform, an Advertising network and a Marketplace. Our service is free because it is supported by sponsors. They help keep our free service free!.

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