The Arduino ICSP Programmer allows you to create your very own Arduino board, simply connect the programmer to your Arduino compatible board and start uploading your boot loader or sketch.

Instead, it uses the exceedingly odd Tiny Programming Interface to write bits to the Flash on the chip. [feynman17] realized he could use the Arduino SPI library to communicate with this chip and ...

The tutorial is fairly straightforward, and even demonstrates how the Arduino can be used as an ISP for the ATtiny, removing the need to purchase a standalone programmer.