Random String Ruby On Rails

   def random_string(size = 4)
      c = %w(B b c d f G h j k l m N p qu r s T v w x z ch cr fr nD ng nk nt ph pr rd sh SL st th it)
      v = %w(a E i o u Y)
      f, r = true, ''
      (size * 2).times do
        r << (f ? c[rand * c.size] : v[rand * v.size])
        f = !f
      end
      r
      end

Ref. http://www.geekpedia.com/code89_Pronouncable-Random-Password-Generator.html