Well, I know this is going to sound odd, but I am very happily married. I wear a platinum wedding band, and I'm actually on my second, because they get so badly banged up and abraded, that after a while, they just look like hell.
So, I was working in my shop a couple of days ago, and I had this idea -- why not make a wedding band out of steel and then harden it. Figured it would have to be stainless or it would rust on my finger, and the only stainless I have in my shop was a slab of 3/8 inch 440C I bought once thinking I would use it to make up some chef's knives. (I never got to it, and have always used straight carbon steels for my knifemaking.) Anyway, I bandsawed out a round (the stuff is tough on saw blades, btw), drilled an appropriately sized hole for my finger, made up a little jig to hold the piece on my little shop lath, turned it to size, and then polished it up. I haven't heat treated it yet, but it actually looks really nice, and even soft, I bet it's much harder/tougher than any gold or platinum ring. Plus, given how much I enjoy working with steel, there's something nice about using it for my wedding band. (Of course, I'm now hosed, because I showed it to the Missus who immediately demanded that I make her a "bangle".) I need to do a bit more polishing (still have some very light tool marks), and then heat treat, after which I thought I'd try tempering it back to a nice spring blue/purple color.
All of which got me to thinking, how cool would it be to do a ring that had a temper line running down the middle of it? In fact, I bet there'd be a market for such a thing. (Maybe I could quite my day job!) I was in a jewelry store recently, and they were getting $400 for a men's titanium wedding band (probably consisting of about 30 cents worth of metal). I can see the marketing slogan already -- the spirit of the samurai in your wedding ring; no two alike... Of course, now that I've outed myself making something other than a knife, Don will probably throw me off the board and never talk to me again.
Anyway, thanks for the info on fire bluing stainless. If it comes out well, and I still have posting privileges, I'll try to put up a pic.