A container has an open top end and a closed bottom end. A chamber is provided between the top and bottom ends. The top end is formed as a neck. The bottom end is formed as a recess. The neck and recess are essentially cylindrical. The neck and recess have a common axis and an essentially common length and diameter. The recess is adapted to receive a neck of another similarly configured bottle/container system. The neck is adapted to be coupled to a recess of another similarly configured bottle/container system.