SGMKtiny-SoftwareSerial

Software Serial works an an ATiny85!

important configure the ATiny85 to run on 8Mhz

avrdude -b 19200 -c usbtiny -p t85 -U lfuse:w:0xe2:m -U hfuse:w:0xdf:m -U efuse:w:0xff:m 

/*
  Blink
  Turns on an LED on for one second, then off for one second, repeatedly.
 
  This example code is in the public domain.
 */
 
// Pin 0 has an LED connected on most Arduino boards.
// give it a name:
int led = 0;

// the setup routine runs once when you press reset:
void setup() {                
  // initialize the digital pin as an output.
  pinMode(led, OUTPUT);     
}

// the loop routine runs over and over again forever:
void loop() {
  digitalWrite(led, HIGH);   // turn the LED on (HIGH is the voltage level)
  delay(1000);               // wait for a second
  digitalWrite(led, LOW);    // turn the LED off by making the voltage LOW
  delay(1000);               // wait for a second
}