int s = 6; // Seed value
background(0);
stroke(255, 60);
randomSeed(s); // Produce the same numbers each time
for (int i = 0; i < 100; i++) {
  float r = random(10);
  strokeWeight(r);
  float offset = r * 5;
  line(i-20, 100, i+offset, 0);
}