Years ago at work, I noticed Dell's emails had an unsubscribe link that went to a "manage account" kind of interface. The idea was you enter your email address,

Years ago at work, I noticed Dell's emails had an unsubscribe link that went to a "manage account" kind of interface. The idea was you enter your email address, go to some kind of "Manage Subscriptions" page, and you could opt out. Unfortunately, you could also see a bunch of Personally Identifiable Information including your first and last names, possibly your mailing address, and other information. I reported this to Dell and got back a very dismissive, abrasive email saying something to the effect of "Well how else are we going to let people unsubscribe?", claiming that they had no other legal option. I just changed all my info to junk and left it at that; eventually they closed that hole, but it wouldn't surprise me if some site exists that still allows people to harvest anybody's information from Dell using nothing but their email address.