original sketch: http://www.openprocessing.org/sketch/114228

int inc;
int num=5;
int []y= new int[num+1];
//int []y2= new int

void setup() {
size(400, 400);
background(255);
inc=width/num;noFill();
// noLoop();

for (int i=0; i<y.length;i++) {

y[i]= (int)random(height/3, height/2);
}}

void draw() {
// background(255);stroke((int)random(100, 200), (int)random(100, 255), 3);
beginShape();
curveVertex(0, height/2);

for (int i=0; i<=num;i++) {
curveVertex(inc*i, y[i]);
y[i]+=(int)random(-10, 10);

}

curveVertex(width, (height/2));
endShape();
}

My Changes: I changed the background color from white to black and the way the curve moves.

http://www.openprocessing.org/sketch/116289int inc;

int num=5;
int []y= new int[num+1];
//int []y2= new int

void setup() {
size(400, 400);
background(0);
inc=width/num;
noFill();
// noLoop();

for (int i=0; i<y.length;i++) {

y[i]= (int)random(height/3, height/2);
}
}

void draw() {
// background(255);
stroke((int)random(100, 200), (int)random(100, 255), 3);
beginShape();
curveVertex(0, 2);

for (int i=0; i<=num;i++) {
curveVertex(inc*i, y[i]);
y[i]+=(int)random(-10, 10);

}

curveVertex(width, (height/2));
endShape();
}