A cordless mouse with an added reed switch is used as a wireless data logger to record every time
the wheel of a trolley completes a revolution. The limitations of the system in terms of maximum
clicking rate and spatial resolution are considered and data obtained from the descent of a trolley
down a ramp at various different angles is analysed in different ways. The data is analysed to
obtain initial accelerations (down the ramp) and subsequent decelerations (on the flat), as well as
maximum velocities, and these results are used to compare the actual performance of the trolley
(with friction) with the theoretical expectation. An agreement of better than 2% on the value of
gravity is obtained. Encouraging agreement on frictional forces (and accelerations) is also obtained
by considering the maximum kinetic energies reached at the bottom of the ramp. This paper includes
the free provision of custom software to record the time history of the clicking of a mouse.