I do alot of blacksmithing and machining which requires alot of specialty tools. So when I run across a simpler and easier metal working project I like to give them a try also.
If you have access to any any pre-1964 50 cent pieces this is a simple but cool project to try. Might be a neat stocking stuffer also. A 50 cent piece will make mens sized ring and a quarter will work for women sizes. Pre-1964 coins were around .925 silver so it is easier to cold hammer then our current cupronickel alloy coins are now.
These are also referred to as "spoon rings" since prisoners used to make them just with spoons, Since most of us do not have as much spare time as prisoners do a hammer will make the job much faster.
http://homepage.mac.com/johnhuber/CoinRing/PhotoAlbum20.html
I will post some pics on mine when I finish them.