"unsubscribe"

One of the best developments in the web this year: one-click unsubscribe links in promotional emails I must have signed up for at some point. Here's the scenario: I get some email from Random Business. I gave Random Business my email two years ago when I was interested in their random thing; I am no longer interested. I want to unsubscribe.
The old way: I'd follow a link in their email to a login screen. If I didn't remember my username and password, which I probably don't since it's been a while, I have to go through the forgot-my-password link, wait for email to arrive, then at least log in again, go to my preferences, edit my preferences, then click save and verify that I really want to unsubscribe.
The new way: At the bottom of the promotional email, there's a link that says "Click here to unsubscribe." In the very best implementation, I click on that link and get a page which says, "myemail@mysite.com has been unsubscribed from all Random Business mailings."
This was a very simple technology to put together, and could have been done a decade ago. By focusing on an everyday annoyance felt by most email users, someone was able to vastly improve the user experience. I won't quite say this builds brand loyalty (I am, after all, unsubscribing) but it does decrease lingering annoyance.
Companies with one-click unsubscribe, I salute you!