This is a question that came up during yesterday's training: "Does CiviCRM offer the feature of sending email change notices? If I go online and change my email address at my bank or broker, notice is sent both to my old and new emails. This gives not only a notice of change but also the chance for me to discover if I've entered the new email address incorrectly."
Any thoughts? If it's not possible now, would this be a good feature request?