For any who might want to drool over their keyboard, these do exist. They are real. But you seldom hear of them, much less see them for sale. a lens with f/0.95. Actually, I seem to remember a Leica with a f/0.90.
I like mine; and even have the fitted case for it. But usually I keep the Nikkor or Canon F1.4 on the cameras. I have the RF version for the Canon 7 and the TV version for an Infrared Camera at work. At work, we used a 1/10,000th Watt laser hooked up to a single mode fiber like a flashlight.