Just thought someone might like this

I was just messing around with one of the example sketches. (Graph)

I thought it turned out pretty cool, so I thought I'd throw it out there.

You'll need an analog input, 8 LEDs (with resistors), and a piezo speaker.

Here's the code:

void setup() {
  for (int n=2; n<10; n++) {
        pinMode(n, OUTPUT);
  }
  Serial.begin(9600);
}


void ledsOFF() {
for (int thisPin = 2; thisPin < 10; thisPin++) {
        digitalWrite(thisPin, LOW);
      }
}


void loop() {
  Serial.println(analogRead(A0));
  int sensorReading = analogRead(A0);
  int ledLevel = map(sensorReading, 0, 1023, 2, 9);
  switch (ledLevel) {
    case 2:    
      ledsOFF();
      digitalWrite(2, HIGH);
      break;
    case 3:    
      ledsOFF();
      digitalWrite(3, HIGH);
      break;
    case 4:    
      ledsOFF();
      digitalWrite(4, HIGH);
      break;
    case 5:    
      ledsOFF();
      digitalWrite(5, HIGH);
      break;
    case 6:    
      ledsOFF();
      digitalWrite(6, HIGH);
      break;
    case 7:
      ledsOFF();
      digitalWrite(7, HIGH);
      break;
    case 8:
      ledsOFF();
      digitalWrite(8, HIGH);
      break;
    case 9:
      ledsOFF();
      digitalWrite(9, HIGH);
      break;
    default:
      ledsOFF();
      }
    
  int thisPitch = map(sensorReading, 400, 1000, 100, 1000);
  tone(10, thisPitch, 10);
  delay(3);
  }


/* Processing code 

 import processing.serial.*;
 
 Serial myPort;        
 int xPos = 1;         
 int Rvalue = 255;
 int Gvalue = 0;
 int Bvalue = 0;
 int CycleCount = 0;
 
 void setup () {

   size(1200, 900);        
   println(Serial.list());
   myPort = new Serial(this, Serial.list()[0], 9600);
   myPort.bufferUntil('\n');
   background(0);
 }
 
 void draw () {
 }
 
 void serialEvent (Serial myPort) {
 
 String inString = myPort.readStringUntil('\n');
 
 if (inString != null) {
   inString = trim(inString);
   float inByte = float(inString); 
   inByte = map(inByte, 0, 1023, 0, height);
 
   if (CycleCount >= 0 && CycleCount < 255) {
     Gvalue++;
   }
   if (CycleCount >= 255 && CycleCount < 511) {
     Rvalue -= 1;
   }
   if (CycleCount >= 511 && CycleCount < 767) {
     Bvalue++;
   }
   if (CycleCount >= 767 && CycleCount < 1023) {
     Gvalue -= 1;
   }
   if (CycleCount >= 1023 && CycleCount < 1279) {
     Rvalue++;
   }
   if (CycleCount >= 1279 && CycleCount < 1535) {
     Bvalue -= 1;
   }
   
   stroke(Rvalue,Gvalue,Bvalue);
   line(xPos, height, xPos, height - inByte);
 
 }
 
 if (xPos >= width) {
   xPos = 0;
   background(0); 
   CycleCount++;
   if (CycleCount == 1536){
     CycleCount = 0;
   }
 }
 else {
   xPos++;
   CycleCount++;
   
   if (CycleCount == 1536){
     CycleCount = 0;
   }
 
 }
 
 }

 */

Let me know what you think!

Enjoy!