The Line is so far definitely the longest version of the Tubes. It stretches over 50 meters. Over that length there are 5 motors dispersed to animate the Line. They create a subtle movement making it look like the work is continuously swinging in the wind even though there is no airflow whatsoever reaching it.
The Line stays very close to its source in the associations it evokes, in that most people very much do think about string when they see it.