Finally! step by step instructions on how to fabricate your own $8 hackduino on perfboard! Never again will you need to dismantle a project just to reuse an Arduino because you can’t afford the $30!
Make your Arduino circuit completely 100% custom. Add LEDs, an opAmp, or any external circuit right on the board! Half the size, and less than 1/3 of the price, this is something everyone who is serious about prototyping and installing with Arduino needs to know how to do.
Here’s the instructable, but maybe you should just check it out at instructables, because the embedding is not fantastic.
Perfboard Hackduino (Arduino-compatible circuit) – More DIY How To Projects