In System Programmers based on the AVR Mega8 chip, including Arduino(tm)

Avrisp protocol firmware (includes support for fuses and locks).

July 2009 How about a shield for the Arduino for use with mega-isp? mega-isp-shield

Older code: Arduino-AVR910: works with AVRDude to copy your hex file to your AVR chip. If you already have an Arduino you can use it to burn projects to other AVR chips (Mega8, Tiny2313, Tiny13, etc).