Dropped cydia tweak brings Activator events when dropping your phone. One event for device in free fall, another event for when device hits the ground.
While this tweak can be used for silly or funny purposes such as having your phone scream or speak when you drop it, it also can have truly useful purposes, such as logging drops (e.g. when you lend/give your phone to someone and want to see if they dropped it, causing potential damage).
Configure options from Settings.