SdFat library with I2C and SoftwareSerial

Other Hardware Storage
9

Are you compiling with 1.5.x so you know your free-memory? If not, you may want to use the freeMem() utility:

// Private function: from http://arduino.cc/playground/Code/AvailableMemory  
int freeRam () {
  extern int __heap_start, *__brkval; 
  int v; 
  return (int) &v - (__brkval == 0 ? (int) &__heap_start : (int) __brkval); 
}

I went back on my notebook and looked at the tinyGPS library and the example:

    while (ss.available())
    {
      char c = ss.read();
      // Serial.write(c); // uncomment this line if you want to see the GPS data flowing
      if (gps.encode(c)) // Did a new valid sentence come in?
        newData = true;
    }

So, perhaps you want to pass the char to the gps.encode() rather than the function.

Ray