Few singers can match Mariah Carey's mind-blowing ability to sing a reputed five octaves -- compared to a piano's seven -- and now the veteran pop diva's vocals have been put to the test. Well, sort of: a cleverly spliced YouTube video shows off the singer scaling, in ascending order, the entirety of five octaves. That's over 65 keys, for those who can do the math, or just make it through the ear-splitting, tea-kettle high notes at the video's end. Mimi herself approves: she Google-plussed the clip on September 30th with the note, "I love my fans! Mwah!!!!"