Digsby, which ties your social networking, instant messaging and e-mail accounts into one interface, just passed 1 million users and started an affiliate program yesterday that pays fans $1 for every new user they sign up. Digsby says its average revenue per user exceeds the cost of finding new ones through the program, so the program generates cash flow. Users sign up on Digsby’s site and then use banners, links and buttons to promote the service.

From Digsby:

A first in the IM industry, the program will pay you up to $1.00 for every new Digsby user you bring. Affiliates can promote Digsby by placing banners or buttons on their blog or website, or by simply inviting their friends with their affiliate link.

DotSyntax, the Rochester, New York-based company behind Digsby is trying to hit a vein and accelerate growth against other social aggregator services like Imo.im, Trillian or Meebo. (By comparison, Meebo says it reaches more than 50 million users through its chat client and a toolbar it launched last month.) The company was founded in 2005 by a group of Rochester Institute of Technology graduates and closed an angel round in 2006.