1: Green Lantern Ring (DC Comics): The ring grants power to anyone with enough willpower to harness it. It has found its way into the hands of Hal Jordan, Kyle Rayner, John Stewart, Guy Gardener, and so many more, granting each of them the power to exercise justice across the galaxy. 

  
2: The Omnitrix (Ben 10): The most powerful device in the universe, an indestructible watch that contains DNA samples from every living organism in the galaxy. One night, it crashed to Earth, and found its owner, Ben Tennyson, a young boy who wanted to be a hero more than anything. With it’s near infinite power, Ben uses the Omnitrix even to this day to perform fantastical tasks, saving countless worlds. 

3: The Stand Meteorite (JJBA): Millenia ago, a meteor crashed to earth. With it came a deadly virus that awakened the potential in the human body for a manifestation of one’s spirit, also known as a Stand. These stands come in many forms, and each one possesses a unique power that matches its owner’s desires. From stopping time, to creating explosives, to traveling between dimensions, each Stand is incredible in it’s own way. 

(Awesome trope) By pure cosmic luck, a powerful alien force finds its way to Planet Earth, and grants what would be an ordinary human amazing powers.