Bueno Mega ISP

Arduino as ISP can work as a normal In-Circuit System Programmer, in plain english, a board that programs other boards to become a microcontroller of a certain type.

You can have designed a board using an external Crystal and in order to "tell" it to the new board "Hey, I placed a crystal close to you. Would you mind using it as your new clock thing?!", you do it using this beautiful piece of electronic device.

It was delicious to have produced this picture. Took me a good 20 minutes arranging the parts, just like therapy to the OCD.

I started from the Bueno Board V2 and removed everything I did not need.

http://www.instructables.com/id/Using-an-Arduino-board-as-an-ISP-via-the-ICSP-head/

Library for the ATtinys http://highlowtech.org/?p=1695