You put the device on your arm.

Here goes, you think, rolling the left sleeve of your flannel pajamas up. You slip your arm into the armband, and pull it up almost to your shoulder, where the elastic keeps it snug against your skin. The largest segment of the armband faces forward, and the entire thing feels slightly cool against your skin. But other than that, nothing seems to happen. For a moment, your heart sinks. I knew it was too good to be true, you think.

And then the large segment starts to glow.

You gaze at the thing, trying to figure out how it works. It's not that the whole segment is glowing; rather, there's a red dot that's softly glowing right in the center of the large metallic segment. You can't figure out how it's doing that -- the segment appears to be completely opaque and seamless, with no holes or transparent areas that look like they could pass light through -- and yet, you can't deny what you're looking at. The fact that you can't figure it out bugs you. The color is striking, like dried blood, but it doesn't pulse, or flash, or really do much of anything. It just glows.

You reason that the thing must do something if it's glowing like this. You hope the note is telling the truth. You roll the sleeve of your pajamas down, and find that the light isn't strong enough to be visible through the fabric, and the shirt is loose enough that the armband itself isn't evident underneath it. And yet, somehow, you feel more powerful just knowing the light is there, even if you can't see it.

Right then, your stomach grumbles, and you remember the eggs and bacon you smelled earlier.