This Instructable will demonstrate the building of a bare bones (and really inexpensive… less than $5) Arduino compatible module that can be put together on a small piece of stripboard and can be used either on a breadboard or independently.
The following links / similar projects were used as inspiration:
* http://www.instructables.com/id/Small-form-factor-DIY-Arduino-on-stripboard/
* http://tinkerprojects.blogspot.com/2012/06/minimal-arduino-on-small-stripboard.html
* http://shop.moderndevice.com/products/rbbb-kit
* http://txapuzas.blogspot.com/2010/07/paperduino-stripboard.html
The schematic is based off of the Arduino Pro Mini (http://arduino.cc/en/Main/ArduinoBoardProMini) and only differs in a few minor (optional) ways:
1. This design uses a more powerful voltage regulator
2. This design uses a more precise crystal (instead of ceramic resonator)
3. This design ditches the reset button (do you really need it?)
4. This design uses a 1k (instead of 10k) resistor for the power indicator LED
For more detail: YABBAS – Yet Another Bare Bones Arduino