A few months ago, before the iPhone was released, I put my email address into an AT&T/Cingular form so I could be notified when it was available for purchase. I later decided that AT&T's horribly privacy (NSA) track record was enough reason not to switch to their service so I'm sticking with T-Mobile for now. I just got an email from them, trying to get me to buy some random crap, and I decided to click on the "Remove Me" link at the bottom of the page. That link brought me to the following page:
It appears that they want your address, cell phone number, landline number, name and email address to remove you from their email list. It turns out that they just want your first and last name and your email address for the removal to work, but the form is certainly not clear about that and I'm sure plenty of folks fill out the whole thing. I didn't put my actual name into the fields, but added something a bit more colorful that I'm sure nobody will actually read. Anyhow, the mass email should really just have a link that removes you, instead of taking you to this horrid form.