Instructables: 2ArduinoSerial

Sender code:
int TXpin = 1;

void setup(){
  Serial.begin(9600);
  pinMode(TXpin, OUTPUT);
}

void loop(){
  int potRead = analogRead(0);
  Serial.println(potRead);
  delay(10);
}


Receiver code:
int serialValue = 0;	// for incoming serial data
int ledPin = 7;
int RXpin = 0;

void setup() {
  Serial.begin(9600);
  pinMode(ledPin, OUTPUT);
  pinMode(RXpin, INPUT);
}

void loop() {
  if (Serial.available() > 0) {
    serialValue = Serial.read();
    Serial.println(serialValue);  // for debugging

    // blink LED
    digitalWrite(ledPin, HIGH);
    delay(serialValue);
    digitalWrite(ledPin, LOW);
    delay(serialValue);

    Serial.flush();
    delay(10);
  }
}