Rocker

Maybe the greatest invention EVER. This universal attachment from OOOMS converts any four-legged chair into a rocker, saving you the time and expense of buying a rocker as well as space that would be taken by that rocker. I’ve waxed lyrical before about rocking chairs, but I’ve never gone into my socio-political theory of how chairs drove the evolution of society. Humankind began with everyone sitting on the ground as equals. Then one person decided they’d like to sit on a treestump while the rest of the tribe sat on the ground, creating a hierarchy and also driving each person to outdo the other in who could get the best seat in the house which culminated in the king sitting on his throne. Hence was born the stratification of human society across all cultures. The rocking chair is the ultimate stage of social evolution. Because there's nothing beyond a throne in which one rocks!