ergio, if you have little brothers and sisters, buy them something! that would be awesome! otherwise, hang on to it. the day will come when you will know exactly how you should spend it. stay safe and make it a great 2013...;-)
If I had $100 right now, I would buy some storage baskets, curtains, a tub of ice-cream, door hangers, a multi-board, an extension cord and if there was any $ leftover I'd save it until I needed something else.