Human Computers
Super intelligence is a difficult to game ability. It's very hard to roleplay as someone much smarter than you (despite what some people think). Moreover it's unlikely any military will allow someone who can cobble together death rays and rocket packs anywhere near the front. Then again a person with a higher intelligence would be able to hide it from their colleagues. Super intelligence is represented (in part) as a huge body of facts and study in a wide variety of subjects. In practice the player character could be allowed an intelligence roll to provide exposition on some obscure facts and be provided any information the referee would expect them to know. In addition the character can be considered to have an intelligence of 18 for most mundane purposes (their stat number is just used for genius stuff). In addition the character is a skilled technician able to tinker, cobble and kitbash a variety of devices from whatever is at hand. Again note that being a fricking geniu