Since I know the digital gyroscope I have a particular interest by this component, due the fact of being used in a lot of modern systems, like smartphones or aircraft industries.
To participate on Lisbon Maker Faire I built a project that used this amazing component, called Self Balancing Robot [SBR].
The SBR helps to understand the principles behind the Segway vehicles. The robot stands in two wheels using the gyroscope inclination readings to position the mass center of the robot in vertical.