In today's environment of rising revenue goals it's hard to imagine the majority of direct marketers overlooking an obvious source of incremental revenue. Given the budget pressure under which most companies operate, it's unbelievable that most direct marketers miss a potential sales resource that is already in place -- a revenue opportunity that is virtually free. Yet that is indeed the case. The highest potential e-mails sent by most companies, literally billions of them, are wasted each year.