Used properly, email can serve to build relationships with customers by providing them with information of interest to them. This is particularly true for B2B, where customers are hungry for usable information about their business.
I created a series of therapeutic-area-specific emails aimed at promoting market analytic products to pharmaceutical clients. Each addressed key issues in the area, and tied those issues to key business questions. These tended to get over 100 downloads, unusually large for our emails.
This multiple-email campaign contrasted inappropriate creativity with solid performance, to promote the reliability of the client without being boring.