Good cross-training workout for basketball?

Does anyone know a good sport to play/workouts to do to cross-train for basketball?

what is waterpolo.. good cross training?

anyone have any idea what that is? i moved from a small school and we didnt have it, to a HUGE school. i lived in that town my whole life, lol so i dont know what it is. my friend said i should cross train and do that, [im a runner], would this be a good sport to cross train with?