When Jim goes to Abby's apartment for the first time, you can read on the intercom :"Sebastian, J.F. #2019". J.F. Sebastian is a character from Blade Runner (1982), set in 2019, and directed by Ridley Scott. Just above is "Scott, Anthony #2012". Anthony Scott, aka Tony Scott, director known for Top Gun (1986), Spy Game (2001) and Crimson Tide (1995), among others, died in 2012 and was Ridley's younger brother.
Michael Ironside's character is likely named after Charles W. Misner, coauthor of Gravitation, an eminent physics textbook concerning Einstein's theory of relativity.
The name of the Irish bar, McTiernan, is in honor of the director John McTiernan.
According to the director's commentary, the scene in which Jim runs out of the lab and encounters Abby was filmed under the Georgia Dome.
During the scene where Jim is driving away from dinner. The bat signal is shown in the sky from one of the buildings.