During the Late Middle Ages, Rabbi Lowe is said to have animated an enormous carved figure, called The Golem, by writing the real name of God on a scroll and placing the scroll under the Golem's tongue, at which point the Golem became 'alive' and able to carry out the Rabbi's orders.  The Golem guarded the Jewish quarter from evil-doers, baby-sat children while their parents worked, carried water from the river, and did numerous other strong-back-weak-mind tasks.  At some point, the Golem went out of control (some say because it was ordered to work on the Sabbath) and Rabbi Lowe had to deactivate it. 

After that, the Golem went to sleep and was moved, still unconscious, to the attic of this building where it remains to this day.  For the safety of all concerned, the attic is off-limits to all but the Chief Rabbi who periodically checks to make sure the Golem is still sleeping.