Subscribe/Unsubscibe.
Whenever I decide to "subscribe" to a company e-mail or news letter I tend to receive a confirmation e-mail before I've even logged off their site.
When I get bored of the crap that they send, I click "unsubscribe" and receive confirmation that my e-mail address will be removed from their databse...."Please allow ten business days for this to take place".
Funny that.