Load up kTurtle and throw this at it. Then change the angle to 120 instead of 90. WHOA!

reset

$angle = 90
$unit = 30

repeat 4 {
  forward $unit * 3
  turnright $angle
  forward $unit
  turnright $angle
  forward $unit * 2
  turnleft $angle
  forward $unit
  turnleft $angle
  forward $unit * 2
  turnright $angle
}