- ...But I Play One on TV: Morgan Freeman reported that during a press conference for the movie, many of the reporters called him "Mr. President".
- Dueling Movies: Set against Armageddon, a considerably more action-packed movie with nearly twice the budget. They were released the same summer, and both did well at the box office, probably because they took such different approaches to the material that they barely qualified as "dueling". The President's speech originally included the line "There will be no Armageddon," but it was taken out as test audiences laughed during the line.
- Follow the Leader: Part of the disaster movie revival of the 90's.
- Science Marches On: When the film was made, scientists believed that a large tsunami would suck back the ocean water, thus briefly looking like an unusually low tide, before the cresting wave crashed over everything. This is shown in the movie when Tea Leoni is killed. However, at the time the movie was made, an actual tsunami had never been filmed. The 2004 Indian Ocean tsunami, which was filmed, showed that no such sudden retreat of water is observed. Instead there is a steady inrush of water, which looks more like the old name for a tsunami—"tidal wave".
- Actually, tsunamis can cause what looks like either an unusually low tide (the old "water retreating rapidly") OR an unusually high tide in the minutes before the wave arrives. It depends entirely on the local geography and the direction the wave arrives in.
- Throw It In!:
- The scene at the assembly were the kid tells Leo that now that he's famous, he'll get lots of sex, was improvised by the actor.
- Morgan Freeman choose to roll up his sleeves during one of his speeches. The director kept it in because she thought it gave him an "everyman" look.
- Unintentional Period Piece: In the early days of the popular Internet. Suffice to say the proliferation of powerful computers, Internet capabilities and personal smartphones tied to social media would make a very different event.
- What Could Have Been:
- Producer Steven Spielberg expressed interest in directing early on. Word of God in the DVD features is that he wanted to adapt the 1930s novel When Worlds Collide but Science Marches On had marched too far.
- The shooting script was 188 pages, and in filmmaking, the rule is that each page represents at minimum one minute of screen time. The finished film is two hours. Yes, a full third of the film ended up on the cutting room floor, mostly character scenes such as Leo visiting the White House, Sarah and her family moving to a parking complex that's been turned into a makeshift shelter, and the Messiah crew drinking vodka once they accept their fates. Quite a few scenes are evidenced in the trailers.
- The script also called for appearances from real-world personalities such as Bill Maher and David Letterman, showing more of how the world would react to an impending comet impact.
- Filming the highway scene was a rather brilliantly handled puzzle. Each truck you see in the scene actually held bathrooms or a food stand. A radio transmitter was brought in and all the cars were told to tune into a specific station for direction - that's how everyone was coordinated.
Trivia / Deep Impact