www.kn34pc.com

The code:
Wayne Holder's arduino project code can be retrieved from the project page:
https://sites.google.com/site/wayneholder/attiny-fuse-reset/ATTinyFuseReset.pde?attredirects=0&d=1
Launch the ‘Arduino IDE’ application and paste/open the .pde patch.

Plug in your arduino
connect the battery to the circuit
compile the patch (check that you are using the correct board, in Tools>Board of the Arduino IDE)
upload the patch
open the arduino console (set to 19200 baud)
You should see this appear in the console:

Signature is: FFFF
LFuse: FF, HFuse: FF, EFuse: FF
LFuse: FF, HFuse: FF, EFuse: EE

In the 'Send' field of the IDE console write anything then click on 'Send', the patch runs and will force the value of the fuses according to the value of the ATtiny detected:

Signature is: 930B
LFuse: C0, HFuse: DF, EFuse: FF
LFuse: 62, HFuse: DF, EFuse: FF

That's it! I hope this will be useful to you!

$regfile = "attiny13.dat"
$crystal = 9600000

$HWSTACK=40
$SWSTACK=8
$FRAMESIZE =8

Config Portb.0 = Output

Do

Portb.0 = 1
Waitms 100

Portb.0 = 0
Waitms 100

Loop
End

// ATtiny13A
//                  _____
// RESET/ADC0/PB5 -|  ^  |- VCC
//       ADC3/PB3 -|     |- PB2/ADC1
//       ADC2/PB4 -|     |- PB1
//            GND -|_____|- PB0

uint32_t t = 0;
bool st = false;

void setup() {
  pinMode(4, OUTPUT);
}
void loop() {
  if ((millis() - t) > 500) {
    st ^= 1;
    digitalWrite(4, st );
    t = millis();
  }
}