In Buddhism, a Conch Shell is blown to call the Gods to listen, when a sermon is delivered. In South Asia, it is called the Sankha. It is one of the eight auspicious symbols in Buddhism. In other Pagan religions, the Conch Shell is blown in their worship of the Ocean.
In the New Eastern Wicca tradition, we can use the Conch Shell to invoke God/Goddess and the Guardians of the Watchtowers of four Quarters.