Marketers and advertisers have long known just how effective direct mailing can be, especially when contrasted to the other similar alternatives, like spamming and teleconferencing. While most direct mail , even some very well designed ones head directly for the trash bins, those that are actually opened by recipients have the potential to be very effective tools for promotions and advertising. For one thing, direct mail can appeal to all the senses and thus, according to what we know of market psychology, can help recipients maintain a lot more information than would be normally possible with alternative channels. The internet can give you more ideas on this practice.