The applicative order Y combinator.

(lambda (f)
  ((lambda (x) (f (lambda (y) ((x x) y))))
   (lambda (x) (f (lambda (y) ((x x) y))))))

or

(define Y
  (lambda (f)
  ((lambda (x) (x x))
  (lambda (x) (f (lambda (y) ((f f) y)))))))

1. has no free variables.
2. has no normal form.
3. work when applicative order reduction.