The previous owner of my car had replaced the factory flag pole with a short antenna. Unfortunately, the antenna looked like something you would find on a cordless phone from 1990 (the flexible ones, that gets curved by the wind from driving on the highway) and the radio reception was absolutely horrendous!

Soo... instead of just replacing it with a factory antenna, I found this on the Saturn Sky forum. Those guys are picking up the antenna from the European Opel GT because it's about 1/2 the height of the factory antenna (it's just a hair above the roofline on a Cobalt). It doesn't hurt radio reception at all (according to the Sky boys) and it was a huge improvement in radio reception/clarity over the antenna the previous owner put on. I had to helicoil the antenna to screw it onto the Cobalt base but I am very happy with the way it turned out.