I don't know about angels, but it's fear that gives men wings.
Fear can be a good motivator. Maybe someone is afraid of losing something good, or gaining something bad. Whatever it is, it can push someone to fight harder than ever before. This isn't a trope about facing your fears and overcoming them, this is about using fear as a catalyst to do the difficult or impossible.
- In Naruto, Sasuke activated his sharigan for the first time when he was scared out of his wits due to Itachi killing their family.
- Astérix and the Normans' plot starts when the Normans take the expression literally and decide they'd like to know how to fly. Being Vikings, they also literally don't know what fear is, and embark to find the biggest coward who will teach them. They eventually learn the feeling when they're threatened with listening to another of Cacofonix's songs.
- There's a Donald Duck story where he needs to win a bicycle race, but his nephews' Training From Hell was so horrible (bathing in ice water at 5 AM, attacked by bees etc) that he falls asleep at the start line even when the gun is fired. Scrooge hides in the bushes and makes a loud buzzing sound, which not only wakes Donald up, but supercharges him to the point that he careens past the other racers without even realizing it.
- In The Horse and His Boy, the horses Bree and Hwin are too tired from their voyage to outrace Prince Rabadash's army, and the author notes that they were pushing themselves only as far as they thought they could. Suddenly, a lion attacks them and the horses get a burst of speed from their fear to escape the predator. The lion is later revealed to have been Aslan, whose attack was a Batman Gambit that he knew would make them go faster.
- In Scrubs, when asked to give a pep rally to JD's residents, Dr. Cox deliberately tries to frighten them by telling the residents it's just a matter of time until they kill someone. Later, when talking with JD who is shaken by the experience, Cox tells him that a little fear is good for a doctor. It keeps you on your toes, or as he put it, "stops you from becoming a crappy doctor".
- Played for laughs in the Stargate SG 1 episode "The Pegasus Project," a crossover with Stargate Atlantis. Rodney Mc Kay from Atlantis has a well-known citrus allergy. When SG-1 needs some calculations five minutes ago, Col. Mitchell threatens him with a lemon Col. Sheppard gave him for exactly that purpose, and Rodney provides the results very quickly.
- In The Dark Knight Rises, Bruce tries making the jump out of the pit several times. His first few tries are with the rope attached to prevent him from falling to his death. After talking with a prisoner who tells him that Bruce's lack of fear of death makes him weak, not strong, Bruce tries the jump once more without the rope, in full fear of falling... he makes it.
- In Max Payne, Vinnie Gognitti is shot and in terror of his pursuer manages to run across several rooftops and jump onto a train to escape, bleeding all the while, leading Max to speculate that it's fear that gives men wings.
- Truth in television, response to a fear stimulus can activate adrenaline, allowing someone to react quicker, and accomplish physical feats they would not have been able to pull off before.