1. An electronic mail apparatus, comprising: a computing device capable of being connected to a network; and an email productivity module, executed by the computing device, and configured to interact with an existing email application executed by the computing device that sends and receives email messages over the network, wherein the email productivity module includes: a content analysis engine, executed by the computing device, configured to analyze a received email message to generate content information representative of a content of the received email message; a prioritization module, executed by the computing device, having at least one prioritization knowledge base implemented on the computing device, the prioritization module being configured to apply the content information to the at least one prioritization knowledge base to determine at least one priority score for the received email message that reflects a relative priority of the received email message as a legitimate email message and to assign at least one priority level to the received email message based on the priority score that reflects a range of priority scores; a message sorting module, executed by the computing device, having at least one sorting knowledge base implemented on the computing device, the message sorting module being configured to apply the content information to the at least one sorting knowledge base to determine a set of suggested folders for the received email message that represent one or more folders in which are stored other emails having similar content and in which a user would be most likely to store the received email message; and a junkmail module, executed by the computing device, having at least one junkmail knowledge base implemented on the computing device, the junkmail module being configured to apply the content information to the at least one junkmail knowledge base to determine a junkmail score for the received email message that represents a probability that the received email message is junkmail, and the junkmail module being configured to cause a user interface of the existing email application to modify a presentation of the received email message in accordance with the junkmail score; the email productivity module being configured to attach fields for the priority score, priority level, set of suggested folders, and junkmail score to the received email message for display by the existing email application; the email productivity module being configured to receive user feedback to the existing email application indicative of a user action taken with respect to the received email message, and to cause the computing device to adapt the at least one prioritization knowledge base, the at least one sorting database, or the at least one junkmail database, in accordance with the user feedback; wherein the at least one prioritization knowledge base is adapted by the computing device in accordance with explicit user feedback in an event that the user modifies the at least one priority level or the at least one priority score produced by the prioritization module and attached to the received email message for display; and wherein the at least one prioritization knowledge base is adapted by the computing device in accordance with implicit user feedback in an event that the user does not modify the at least one priority level or the at least one priority score produced by the prioritization module and attached to the received email message for display.