In the German science fiction series Perry Rhodan, positronic brains (German: Positroniken) are the main computer technology; for quite a time they are replaced by the more powerful Syntronics, but those stop working due to the increased Hyperimpedance. The most powerful positronic brain is called NATHAN and covers large parts of the Earth's moon. Many of the larger computers (including NATHAN) as well as the race of Posbis combine a biological component with the positronic brain, giving them sentience and creativity.
Read more about this topic: Positronic Brain, Appearances in Science Fiction