Daniel Tammet can recall 22,514 decimals of pi and perform huge mathematical calculations instantly in his head. He's also a highly skilled language learner: he is fluent in seven languages, and is even coming up with his own language. Speaking multiple languages is one thing, but to do it at Tammet's pace is distinctive. He learned Icelandic, for instance, in just seven days.
Though Tammet isn't unique in his savant abilities, he is unique in his ability to explain his thought process. Usually, savants can't describe how they can do what they do. Tammet, however, describes seeing numbers as shapes, colors, and textures that come together in his mind's eye to instantly calculate an answer to a problem. Scientists don't know how people acquire savant syndrome, but they believe Tammet's ability to explain what's going on in his head can help them better understand this amazing condition. For more incredible savant stories, check out the video below.