Meetup.com and as a result the New York Tech Meetup are egregious offenders of not providing 1-click unsubscribe. They take it another step further and make it extremely difficult to unsubscribe on the website too.
Meetup.com also send out "A waitlist is available for [event]" e-mails - perhaps the most unhelpful e-mail possible, and as far as I can tell the only way to turn them off is to turn off everything.
