About 8 minutes in, just before Tommy (Steve Buscemi) drives up to the garage where he has dialogue with Johnny the mechanic (John Ventimiglia) about his car's problem, he passes a parking lot. Walking towards the lot are three men wearing dark suits walking together in the distance. It was originally thought of as Buscemi's homage to his first big movie role, Reservoir Dogs (1992), but when asked, Buscemi said it was just a coincidence.
The trivia item below may give away important plot points.
After the original Trees Lounge shut down, Steve Buscemi bought the sign and restored it to use for his movie, although he was not able to use it. He then gave it to a woman who worked at Trees Lounge for 40 years.