The YIVO Institute for Jewish Research makes many of the 24 million items in its archive available online, but there's an "electric moment of actually touching a document," says its executive director. "My first was when Lenin's party card was put in my hand." (Patrons are urged not to touch the documents. This is not some sort of scholarly petting zoo.) Music: Jardena Gertler-Jaffe, Bethany Pietroniro.