I'd be willing to bet that most of us have upholstered headboards. It's understandable; it's quite comfy leaning against that padding while sitting up in bed. But I have to say that I do find metal campaign style beds quite fetching too. I come across photos of them frequently in my old French decoration books, and let me just say that they look really dreamy. If you have a moderately feminine bedroom, the simple, masculine shape and metal construction (usually steel) offer an interesting contrast. If your bedroom is more on the manly side, then these beds offer an additional shot of testosterone. And if you're a die-hard girly girl, then these beds probably aren't for you.
Most of the examples that I've found are daybeds like the one featured above, though I have seen a few Empire style headboards and footboards as well. I think that what I like most about them is that pleasing X motif. It's simple yet emphatic looking. And if you're worried about comfort, I would suggest piling some large Euro pillows against the headboard and calling it a day... or night.
I do admit that the footboard is a little imposing looking for such a small bed, but regardless, it's a canopy bed with a nice architectural presence.
A 1950s example. The combination of the metal bedframe and that leopard print fabric (where have I seen it before??) is a little odd, but for some reason I like it.
Oomph's Southport headboard is not quite Campaign nor Empire, but it is an interesting alternative to the padded headboard. It's evocative of a garden gate.
If you refuse to let go of your upholstered headboard, then what about this brass and steel mirror, attributed to Bagues, that is available through Parc Monceau? It's similar in feel to the campaign beds, and yet you don't have to get cozy with it.