The Nitehawk Shorts Festival is April 2nd through 6th this year. They are holding their opening and closing at their larger venue, the Prospect Park location.
The Thursday night schedule has 2 blocks, Music Driven and Midnite, but being held at the original Nitehawk Cinema in Williamsburg. Both of those blocks are already sold out. Friday is a break. Saturday has 2 blocks as well. They are both matinees and are divided between locations. The Williamsburg one is sold out, while there are still tickets for Prospect Park.
Sunday closes out the festival with 2 blocks at Prospect Park. There is a No Budge block at 11am followed by the Closing Nite block at 7pm. Basically, everything in Williamsburg is already sold out, so get a ticket or two for screenings at the Prospect Park theater.
Some of these films are made by local New York filmmakers, so there's a good chance you can meet them at the festival.