This page provides some information about the design of my arduino watch.

Description of watch

arduino mini pro 3v 
nokia 3310 lcd screen
rechargable lithium coin cell battery
plastic case for memory card
paper with conductive traces (for connecting screen to arduino)

The hardest part of making the watch is to connect the screen to the arduino.  Below, you can see how the paper with conductive traces is soldered to the board.

The spacing of the conductive traces does not match the spacing of the cell phone connector, so you have to test the wires to figure out which is connected to which.

The screen is very fragile, so I first superglue it to the plastic cell phone backing that comes with the screen (I usually break a few screens).  After that is secure, a second piece of plastic is use to hold the conductive paper against the screen connector.  I use clips to hold it together while I test the connections between the screen and the board.  When it works, I super glue the plastic strip to the plastic cell phone backing.  This allows me to take out the conductive paper thing when necessary.

The pictures above come from a version where I tried to put the arduino upside down.  But since my plastic case for the watch is too small, I eventually flipped the arduino.

The pde file that is attached below is a minimal test program that will allow you to see if your screen is working.  It creates a random dot pattern.  It is necessary to change these lines to conform to your setup.

int SPI_CLK_PIN        =        6; //  PB5  2  CLOCK
int SPI_MOSI_PIN       =        5; //  PB3  3  Serial   line
int LCD_DC_PIN         =        4; //  PB0  4  Data Command
int LCD_CE_PIN         =        2; //  PB2  5  /CS   active low chip select ??
int LCD_RST_PIN        =        1; //  PB4  8   /RES RESET

I will post more later.  Please let me know if you are using this information or if you have other questions.

This video shows it playing pong against itself and conway's game of life.  Not very clear unfortunately.

Links that I used to make the watch:
Franklin Chang,
Apr 29, 2011, 2:10 PM