उंदीर आला ! (a mouse/rat has come!) ~ hearing this, it is not surprising that everybody runs around, trying to get away from this pest. This very pest, though, is the mount of Lord Ganesha and you will always find a mouse at the foot of a Ganapati idol, quietly sitting there. Many temples of Lord Ganesha also have a sculpture of a mouse in front of the temple gates, signifying the mouse as a guardian (one example: the Ganapati Moreshwar temple).
Do you know why the mouse, considered to be something really horrid, is Ganapati's vehicle ?