Dan Brown tells his son Richie about falling in love with Laura, but John C. Reilly was actually telling Jack Rovello the story of "Jack and the Beanstalk" so the young actor would appear interested. The actual dialogue was dubbed in later.
Nicole Kidman loved wearing the prosthetic nose and wore it in private too, mainly as she was undergoing a divorce from Tom Cruise at the time and was attracting a lot of paparazzi interest. Much to her delight, by wearing her fake nose out and about, she found she could easily evade the paparazzi as they didn't recognize her.
During the editing stages, producer Scott Rudin received a call from author Michael Cunningham requesting to see some of the footage. Cunningham's mother (on whom the character Laura Brown was originally based) was entering into the final stages of terminal cancer and Cunningham dearly wanted his dying mother to see something he had written committed to film. Rudin hastily assembled twenty minutes of footage and had it sent over to the Cunninghams.
Nicole Kidman decided not to imitate Virginia Woolf's actual tone and voice because she feared people would find it comical.