Shock Absorbers are extremely useful. They reduce the fall damage by the amount of energy they are allotted. This is customizable by the GUI available in the Tinker Table. One might notice a sound when landing, this means that the fall would have normally taken damage, but the shock absorbers have nullified it. Shock absorbers are particularly useful when exploring deep ravines, as it enables you to jump down with heroic fearlessness; fall damage will bother you no longer. Shock absorbers need 2 servo motors and 2 wool, so it's extremely cheap for it's usefullness.