@zephzoid: One bucket of sourdough starter survived the 1906 San Francisco earthquake and still flavors every loaf today. Isidore Boudin built the mother dough from wild yeast in 1849. When the quake set the city on fire, his widow Louise grabbed it in a wooden bucket and ran. Boudin still will not sell or share a piece, saying its wild yeast cannot be reproduced elsewhere. Skip the trademarked starter and find independent bakers on Localize. Sources: SF Examiner, SFist