http://www.freecodecamp.com/kkas 's solution for Bonfire: Chunky Monkey

bonfire-chunky-monkey.js

// Bonfire: Chunky Monkey
// Author: @kkas
// Challenge: http://www.freecodecamp.com/challenges/bonfire-chunky-monkey
// Learn to Code at Free Code Camp (www.freecodecamp.com)

function chunk(arr, size) {
  // Break it up.
  var i, len = arr.length, newAry = [];
  
  for(i = 0; i < len; i += size) {
    newAry.push(arr.slice(i, i + size));
  }
  return newAry;
}

chunk(["a", "b", "c", "d"], 2);