The eclectic one-item-at-a-time online store Woot! passed the 1 million follower mark in July. I just learned about it in their August email newsletter; today they have 1,197,831 followers and 2,671 tweets.

The Woot! Twitter feed advertises the sale of the day, which is available until it is sold out or until 11:59pm Central, when it is replaced with the next day’s item. There are usually two tweets a day, with the second being identified with a “Last Call” alert.

This is the same model used by AmazonMP3 (992,383 followers, 645 tweets), although Amazon has more than one offer each day. It is similar to that used by Dell Outlet (1,097,064 followers, 663 tweets). The DellOutlet account differs from the other two, however. In addition to the posts advertising products, Dell’s tweeter (@StefanieATDell) posts contents, retweets and @ replies. Dell HomeOffers, which is a sale posts only account like AmazonMP3 and Woot, has only 3,412 followers, but it is also a newer account with only 357 tweets.