Return only Accel values

To get the value from 0, you need to subtract a 'base' value.

For instance you could do:

Puck.accelOn();
var accZero = Puck.accel().acc; // get the base value when we start up
Puck.on('accel', function(data) {
  console.log(data.acc.x - accZero.x);
});

If you want to stop the values moving so fast, you can do an average:

Puck.accelOn();
var accZero = Puck.accel().acc; // get the base value when we start up
var avrX = 0;
Puck.on('accel', function(data) {
  avrX = (avrX*0.9) + 0.1*(data.acc.x - accZero.x);
  console.log(avrX);
});

You can change values to get a slower movement but they must always add up to 1, so 0.9/0.1 or 0.8/0.2(faster) or 0.95/0.05(slower)