/*
Concrete Crickets Arduino Code
Michael J. Dory
http://www.doryexmachina.com
Written 04.11.07, revised 11.02.07
(thanks to code from Tom Igoe, Clay Shirky and Rob Faludi)
*/

int RangePotPin = 5; // Analog input pin that the rangefinder is attached to
int RangePotValue = 0; // value read from the pot

int MP3Pin = 12; // the pin that the relay controlling the MP3 is attached to

int blinkyPin = 13; // the pin that the reference LED is attached to

int onOffPin = 11; //the pin that the speaker attach/kill switch relay is on.

void setup() {
// initialize serial communications at 9600 bps:
Serial.begin(9600);

// set pins for output
pinMode(blinkyPin, OUTPUT);
pinMode(onOffPin, OUTPUT);
pinMode(MP3Pin, OUTPUT);

// initialize both pins at low
digitalWrite(MP3Pin, LOW);
digitalWrite(blinkyPin, LOW);

delay(100);

// turn MP3 Player on, blink pin 13 for reference
digitalWrite(MP3Pin, HIGH);
digitalWrite(blinkyPin, HIGH);
delay(5000);

// take both pins low again
digitalWrite(MP3Pin, LOW);
digitalWrite(blinkyPin, LOW);

delay(100);

// blink LED three times quickly to show mp3 player is on
blinky();

// start playing the MP3
delay (2000);
digitalWrite(MP3Pin, HIGH);
digitalWrite(blinkyPin, HIGH);
delay(500);
digitalWrite(MP3Pin, LOW);
digitalWrite(blinkyPin, LOW);

// blink three times to show that the MP3 player is playing and setup is complete
blinky();

// end setup
}

void loop() {
RangePotValue = analogRead(RangePotPin); // read the pot value
Serial.println(RangePotValue); // print the rangefinder value back to the debugger pane
delay(10); // wait 10 milliseconds before the next loop

if(RangePotValue <= 125) { // if the rangefinder detects something in range
digitalWrite(blinkyPin, HIGH); // turn the light on
digitalWrite(onOffPin, LOW); // turn the speakers off
Serial.println(”detected”); // print “detected”

delay(100);
}
else {
digitalWrite(blinkyPin, LOW); // if the rangefinder doesn’t detect anything
digitalWrite(onOffPin, HIGH); // leave the speakers connected
Serial.println(”not detected”); // print “not detected”
}

}

void blinky() {
int i;
int blinks = 0;

for (i=0;i<=blinks;i++) {
digitalWrite(blinkyPin, HIGH);
delay(500);
digitalWrite(blinkyPin, LOW);
delay(500);
}
}

for (i=0;i<=blinks;i++) {
digitalWrite(pin, HIGH);
delay(delay);
digitalWrite(pin, LOW);
delay(delay);
}

Should cut the code in half, and make the blink handling more flexible, no?