Factual error: When Tom Cruise is going to defibrillate Keri Russell to disarm the bomb in her head, no defibrillator takes 30 seconds to charge to 150 joules. Most go to 360 joules and if they are not charged in 10 seconds the batteries are depleted enough that they won't charge at all.
Trivia: The scene in which Julia brings Ethan back to life is copied almost identically from the scene in "Lost" (Director JJ Abrams' hit TV show) where Charlie is brought back to life. Incidentally, you can hear the "Lost" music played throughout the show, most noticeable when Davian is about to pick up the gun to kill Julia.
Trivia: One of the reasons why they chose the HK G36 as the rifle Ethan uses in the bridge scene is because it made the scene with Ethan throwing the rifle over the hole blown in the bridge possible in the real world. The G36 is maybe the only rifle in the world that is purposely designed to endure a 2m fall without misfiring. Any other rifle would have ejected its magazine if dropped.
Question: When the IMF-team fake the DHL-van breaking down, some drivers from other cars join in on the shouting that ensues. Ethan looks at a man shouting something, and he responds by raising his arm at the man with his handpalm up. What exactly does it mean in Italy when you make that kind of gesture?