Cheap$kate: FREE events in NYC this weekend

Sonia Sotomayor
We know you're not supposed to judge a book by its cover. But what are we supposed to do when we have to cover a judge's book? While we figure that out, you should hear Supreme Court Justice and Bronx native Sonia Sotomayor talk about her memoir, "My Beloved World." (Sunday, 2:30 p.m., FREE, Barnes & Noble Union Square, 33 E. 17th St., 212-253-0810, bn.com)

Art

'The Arches of Hope'
Help raise awareness of the HIV/AIDS epidemic affecting a new generation by stopping by "The Arches of Hope" interactive art installation at The OUT NYC hotel, opening tomorrow and running through April 18. Proceeds from the opening benefit reception Thursday (tickets cost $125) will benefit Lifebeat: Music Fight HIV/AIDS and MTV Staying Alive Foundation. (Opens Friday, FREE, The OUT NYC Lobby, 510 W. 42nd St., archesofhope.com)