Yeah, spoons come in 16" ($485 a pop, though). Get light wheels, they say for every pound lighter your wheel is, its like your car being 5 lbs lighter (somebody actually figured that one out I guess).

Reallistically, it all depends on what your willing to do away with, you could take off your power steering pump, remove door/interior panels, pull up the carpet, get non-power mirrors/windows, go under the car and chisel off all that sound deadening gunk underneath, of course if you did all that your car would be faster, but much worse for impressing the skirts.