lagniappe

lagniappe or lagnappe n something given beyond what is strictly required; a gratuity. [Origin from Louisiana French, from American Spanish (Quechua yapa addition)] Chambers, 1998

Aside from its interesting American French/Spanish origins, and aside from the idea that it might mean no more than leaving a tip, I really like the primary meaning: namely one of polite kindness. It feels like a very gentle word (the gn is soft, like in lasagne) and a remnant of more courteous times. Lovely.