To be fair, the protocol for unsubscribing from the chevelle list is not as simple as most similiar lists, where they print the unsubscribe info at the end of every email. I happen to know how to do it because I'm a neatness freak and saved the instructions for it in a special mail folder. Even so, I'm not completely sure just what you're supposed to do.
As I understand it, you're supposed to go to the URL: http://chevelles.net/mailman/options/chevelle-list_chevelles.net/ adding your email address after the last slash, and then follow your nose.