What are some examples of science fiction predictions that have come true that amazed you?

I recently read Isaac Asimov's Foundation series and suddenly realized that he had predicted devices similar to the iPad as early as the 1950s. There must be many examples in science fiction where the author's predictions have come true. Can you share some science fiction predictions that you think are "Wow, the author was practically a prophet!"? Preferably examples that seemed absurd at the time but have now become a reality.