Abstract: A multi-purpose device, the device including a tube holder for holding tubes; tube driving apparatus for rotating the tubes in the tube holder, the tube holder having spaces for accommodating the tubes such that each one of the tubes can be placed in a separate one of the spaces; the spaces having shapes and sizes providing free rotation of the tubes within the spaces about longitudinal axes of the tubes; the tube driving apparatus having touching engagement with walls of the tubes and pressing the walls of the tubes against the tube holder; and friction between the tube driving apparatus and the walls of the tubes being greater then friction between walls of the tubes and the tube holder.