Rebecca Sealfon, born R-19b at The Sealfonic Innovations Research and Development Facility in White Plains, New York, is the world's greatest speller. She can spell words you've never heard before in your life. She can spell words you've never imagined possible. She can spell words that you've just made up randomly. Seriously, write a string of letters on a napkin that vaguely resemble a word. She can spell that.