Yes, there is only the Public Advocate runoff today. Turnout will be unbelievably abysmal.
Which means two things: (1) your vote means more than ever and (2) you'll be in and out in seconds rather than minutes. Seriously, I was in and out of there in under a minute.
Bonus: someone left several boxes of books and videos by the Carroll Gardens library polling site entrance on Union. So feel free to treat yourself after you vote.