Found on the web: Gina Lofaro explains the user experience of finding it hard to unsubscribe. What galls me is that the list owner actually decided it was wise to argue the law with an angry subscriber. Knock that off! If she wants off the list, say OK, thank you, and it has been handled. She might not be a lawyer, but neither are you, and if you want to have any hope of selling her something ever again, maybe don't be snotty to her when she needed your help. And the subscriber is actually right -- that email SHOULD have had an unsubscribe link or option specified in the email message.
Love that e-card.