Dell says it has surpassed $3 million in sales attributed to Twitter, and the online social network, which has yet to make a profit, is watching closely.

Dell sells refurbished systems through Twitter at @DellOutlet, which the computer maker says has more than 600,000 followers. Since launching @DellOutlet in 2007, the company has taken in more than $2 million in sales directly attributed to Twitter and another $1 million from people who start at Twitter and then move on to buy a new computer somewhere else on the Dell Web site, Stefanie Nelson, who manages the Twitter account, said in the corporate blog late Thursday night.

Dell's Twitter sales amount to less than a sliver of its multibillion-dollar annual sales. However, its success in enticing buyers shows that money can be made through the social network in which people post and subscribe to mini-messages, called "tweets."

Dell's success is being watched closely by Twitter, which has yet to establish a business model for making money. The social network has said it plans to eventually draw revenue by assisting businesses in promoting and selling products through Twitter. In addition, the company is looking to draw a profit through search, capitalizing on the real-time nature of its messages. How search would be monetized is not yet clear.

While not providing specifics, Nelson told USA Today that Twitter is soliciting feedback from Dell. In addition, the two companies are testing new features.

In making sales through @DellOutlet, Dell sends tweets to subscribers, telling bargain hunters the latest available refurbished systems. The company also messages coupons and clearance events.

The strategy has taken @DellOutlet to the top 50 most followed Twitter users, according to Dell. Such standings are tracked on a third-party Twitter monitoring service called TwitterCounter.

Other top 50 Twitter users includes brands like @Zappos, @Woot, @JetBlue, and @WholeFoods. As of March, Twitter.com reached 9.3 million visitors, according to ComScore Media Metrix.

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