Thanks for the info @CrossRoads.
It seems that I have 100ms in between buffering of the MP3 so I guess it'll be fine.
Now I'm gonna throw in a Triple Axis Accelerometer Breakout - ADXL335 ( SparkFun Triple Axis Accelerometer Breakout - ADXL335 - SEN-09269 - SparkFun Electronics ).
Since both the Accelerometer and and RTC uses I2C will I run into any problem? I haven't got any experience using I2C bus, but according to this ( Tutorial: Arduino and the I2C bus – Part One | tronixstuff.com ), more then 1 I2C device can be connected to the same bus (SDA and SDL). Any suggestions from experience will be appreciated.
Thank you.