Twitter: How are you getting followers?

Retailers are trying to get the word out about their Twitter accounts in different ways. For example, Express lets shoppers know via in-store receipts and Whole Foods has signage outside some locations. Meanwhile, many companies are posting Twitter logos on the top of their sites (like CSA!), and others, such as Famous Footwear, have the well-known Twitter bird on the bottom of their homepage.

Everyone is still trying to figure out the best way to build their follower base. How are you getting the word out? What strategies do you think work best? And finally, where do you think the logo should go -- at the top of a homepage? The bottom?