I can believe this:
The way you type is as unique as your eye colour or speech patterns and can be used instead of a password to protect your computer, researchers at Louisiana Tech and Penn State say.
The technique focuses on keystroke timing, but if it also analyzed typo patterns, I imagine the technique could be even more accurate (though of course much larger samples would be required). Whenever I intend to type “elephant”, half the time my first attempt is spelled “element”. It’s a finger macro! (Uh, not this kind…)