Originating in Nepal and India, the Hindu holiday Diwali includes decorating homes with special oil lamps called "diyas" to welcome Lakshmi, the goddess of prosperity. It's also called the Festival of Lights (Gee, sound familiar? Christians haven't co-opted that one have we?) and according to Wikipedia, the festival preparations and rituals typically extend over a five day period. In the Gregorian calendar, Diwali night falls between mid-October and mid-November.