This how-to takes you through all the steps of making your own arduino on a perfboard or perfduino! Arduino microcontrollers are great for learning about physical computing and are very useful for rapid prototyping. Arduino’s simple programming language makes it a favorite of hobbyists and diy-ers around the world. Because arduino boards range in price from 30 to 70 dollars, it can be very cost effective to make your own. This lets you customize the layout of the board and brings down the cost so you can embed your perfduino in a final iteration project without losing your precious professionally made arduino board you had to wait so long for by the mailbox. The perfduino in this tutorial is designed to closely mimic the original arduino functionality without any specific project layout in mind.
Perfduino: Build Your Own Arduino Microcontroller! - [Link]