http://readable.sourceforge.net/

from this:

(define (factorial n)

  (if (<= n 1)

    1

    (* n (factorial (- n 1)))))

to this:

define factorial(n)

  if {n <= 1}

    1

    {n * factorial{n - 1}}

and if you want to use parens, they just work (you can mix and match the two whenever you want without issue). That said, even with such things available, most lisp programmers opt to use parens.