I had some free time around the end of 2012 and a few parts lying around so I decided to put them to use. As an extra I also wanted a reason to practice soldering.
To have something to begin with
first I checked if I have all the parts that are necessary.
- Atmega328p – check
- Female pin headers – check
- Cable – check
- DIP socket (optional) – check
- 6mm switch – check
- 16mhz oscillator and capacitors – check
- LEDs – check
- resistors (1k, 10k, tht* will also do) – check
- some interface to program – male pins for rx,tx,gnd,5V – check
- leftover perfboard – check
The design itself is a straight copy of the Arduino Duemilanove but I did not add the voltage regulators and the FTDI chip. The only special part that you cannot find in any store is the Atmega chip but the others are widely available and cheap.
Total cost: ~6 euros and a few hours of soldering.
The first image shows that I used my cheap USB2RS232 converter (ebay) to program the board.
First I used this tutorial to burn the Arduino bootloader onto the Atmega chip then I placed my Arduino Duemilanove in front of me and copied it’s layout on the perfboard. All that had to be done after this is soldering pieces of cable on the background.
This figure did most of the job for me 🙂 
The design may not be perfect but it worked out so far. If you see any imperfections please do tell 🙂
References
*tht : Through Hole Technology
http://www.ladyada.net/make/boarduino/
Flesh and machines 