Often described as a hollow sphere spun from what looks to be copper wire, Alighieri's Cradle is one of the more commonly accepted to exist of the old-world artifacts. Floating in the center of the bronze construct is a small mote of light, in a shifting yellow, red, and orange, like a vastly miniaturized sun. It is. A sun, that is. Maintained within the device as a power source. Even the most inexperienced Ace has heard of it, and almost everyone has seen it depicted somewhere. Whatever the device's original purpose was has been lost to time, but humanity is nothing if not resourceful. It might have powered a city or even a country at some point. Lacking the technology to take advantage of that, however, it makes a good weapon. When properly deployed, a process that requires some testing (dangerous, when you're handling the power of a sun, as you might imagine), a ray of concentrated solar material can be ejected from the device in a sort of ray. The size and shape of the ray is variable, but its destructive might is universal. Whole squads of infantry, tanks, bunkers, city walls, starships, even entire city blocks are cut in half or vaporized entirely. Thankfully for the world, such a device tends to inspire ambition and fear in equal measure, making sure most don't get to use it for long. The Cradle regularly changes hands, mostly because someone manages to kill the current holder and take it for themselves. Just has as often, these confrontations take place in unknown or hard-to-reach locations, and the device is lost to everyone for a time, much to most of our relief. Inevitably, it is always found again. Hard to avoid with such a well known piece of old world tech.
Unique, though it's widely theorized that there should be others out there.