What's stopping you from saving it for something that you will want in the future? :P
Idk what i'm supposed to do with so much money xD
Books, games, movies, entertainment in general can be a good option.
Will's option is sound. (i love your disruption of the smiley btw)
Candy is also a sound option. Or chocolate, or tea or ... hmm. Food is an entertainment.
Keeping it for a gift for a close friend/family might be a good idea too.