How Customer Data Can Help Build Better Marketing Campaigns Online service Windsor Circle uses customer purchase histories to help small businesses improve their email marketing.

While online giants like Amazon endlessly analyze customer data to recommend new products, offer promotions and generate sales based on buying history, such sophisticated customer relationship management has been beyond the financial reach of most smaller e-tailers.

Windsor Circle, a new plug-and-play service, is changing that. It extracts customers' shopping-cart data and integrates it with e-mail marketing platforms such as ExactTarget, Constant Contact and VerticalResponse, allowing small shops to create targeted e-mail campaigns based on buying patterns and other trends. Call it the new era of big data writ small.

Because Windsor Circle allows its clients to segment customers and create targeted promotions, merchants can easily reward big spenders, send coupons to folks who haven't purchased in a while, recommend replenishment orders or suggest complementary products. Business Supply, an online office products company, used Windsor Circle to pull a list of its most recent, most frequent and highest-spending customers, then send them a thank-you e-mail and a $10 coupon. The blast generated a nearly 400 percent ROI.