I've wanted a certain non-essential piece of camping gear for a while now: a sleeping bag liner. You can buy them for as little as $30, or for as much as you have cash to spend. They usually come in cotton, fleece, silk (or "silky" material), each one being good depending on what you want to do with it. I wanted something to keep the inside of my bag clean (liners are more washable than sleeping bags), to add a bit of warmth to my bag, and to have a lightweight bag for summer camping.
Shortly before Christmas, I found fleece blankets on sale for about $3.50 each. I don't know how much a comparable amount of fleece fabric would cost, but that seemed a pretty fair deal to me. So I picked up two. And I also picked up a 36" double-zip zipper.
I had a design in mind similar to this one, which I referred to for inspiration. Instead of sewing straight across the feet, I sewed a circle onto the feet to make a nice, big foot box, because I have big feet and they don't like being too crowded when I sleep.
All in all, it was pretty simple sewing except for the zipper. We may have a zipper foot around here somewhere, which would have made things much easier, but I was too lazy to go hunting for it. Still, I have had zero experience with zippers, and they're not the easiest things to navigate, as I understand it. But the zipper zips, which is what I was going for. We'll see how it holds up to regular use.