Something like a key ring should work. But, if you have to replace the zipper, I saw a great way to do it. Instead of ripping the old one out, this person cut it out as close to the stitching as possible. The she sewed the new one in with the new stitch line right next to the old. It makes the zipper a tiny bit more visible and gives 2 rows of stitches as 'topstitching', but it is a sweatshirt and it is so, so, so much quicker and easier.