Filming only took four weeks.
In real-life, the website that Dr. Bedlam mentions ("professorbedlam") linked directly to the official Fox movies website. The site has since lapsed.
The architecture office work space in the movie is the actual office of renowned architect Robert A.M. Stern in New York City.
The "castle" in Matt's fish tank is a simplified model of Frank Lloyd Wright's famous design for a house called "Fallingwater".