Go out and have fun burning up the tires
...then you can put that $800 towards a new set of tires!!
Otherwise I would put it in the bank towards a future more expensive mod like LT Headers that will really wake the car up!! I wouldn't spend $800 just to spend $800. Make sure you are getting something you really want.
As others have said too. Put it towards a few track days. You will enjoy the car like you never have before and really start to appreciate your car and then you'll really figure out where you want to spend money on mods for the car.