Toward the beginning of the movie when Gia (Angelina Jolie) first goes to New York to meet with Wilhelmina Cooper, she goes in to the office and speaks to the receptionist. When she gives her name,the receptionist says, "G-what?" So Gia pulls out a switch blade and begins to carve her name on the desk. Here's where the slip-up occurs: watch her carve her name, in the first shot she is carving the letter "G" and she messes up slightly on the carving so it looks like a number 6 instead; then the shot jumps to something else for a few seconds, then back to her name carved on the desk. This time the letter "G" looks normal, not like a 6. It's not a major error, but it is pretty obvious once you're aware of it.