MicroView Digital Compass
Contributors:
AGlass0fMilk
AGlass0fMilk 
Resources and Going Further
There are a many more cool projects you can make with the MAG3110 sensor. If you combine the MAG3110 with a few other sensors, you can make a variety of projects that involve location and orientation sensing.
Check out Shawn Hymel's Adventues in Science: Using a Magnetometer as a Compass and example code for ideas:
For more sensor fun, check out these other great SparkFun tutorials:
INA169 Breakout Board Hookup Guide
How to interface with the INA169 Breakout Board to measure current.
AD8232 Heart Rate Monitor Hookup Guide
Learn how to create your very own heart rate monitor.
SoftPot Hookup Guide
Equip your Arduino project with a sliding soft potentiometer to monitor position or adding linear control to your project.
Sending Sensor Data over LoRa
This tutorial will show you how setup a simple peer-to-peer connection to send and receive sensor data using LoRa.