Besides the zig zag and zipper foot (and walking foot, of course) I also own a piping foot which I find very helpful, and at a foot for narrow hems, which work great. Recently I used the overcast foot and loved how nice it makes an overcast edge. I have a cording foot and I think I used it once. Also, there is a foot specifically for sewing on buttons which is helpful, gripping the button instead of sliding off of it. And there is a free motion foot, which is something I need to practice.