Music lovers, rejoice: The pianos are coming back! Specifically, the Pop-Up Pianos that Sing for Hope—an organization that “mobilizes professional artists in volunteer programs that benefit schools, hospitals, and communities”—refurbishes, gets artists and kids to decorate, and then places in parks and other public spaces around the city. (If you missed it last summer because you were holed up in Amagansett, the pianos were a wonderful addition: They’re there for anyone to step up and play, and play people did.) This summer, there will be 88 pianos (up from 60 last year, with 28 baby grands stationed in indoor public spaces), and they’ll be out from June 18 to July 2. Below Canal Street, a.k.a. BeloCa, you’ll be able to find them at Tribeca Park, City Hall Park, Washington Market Park (new this year!), the north end of Battery Park, Stone Street, and Columbus Park. Last night, Sing for Hope co-founder Camille Zamora hosted a party and her swell Walker Street apartment, where guests such as moi—I’m turning into Hedda Hopper—sipped, nibbled, listened to music, and were led on a tour of the space in the AT&T Building (32 Sixth Ave.) where the pianos are worked on. Sing for Hope could still use volunteers to “buddy” with the pianos in Tribeca Park and Columbus Park. You don’t have to do much other than check in once a day and cover the piano with a tarp in the event of rain.