Okay, so no sandbox this time. I'm too tired and too pressed for time (going on vacation soon). But I have another idea, and I'd like to see what people think. This one is ported over from a dream I had, many years ago.
The object is some small carved stone or something. It generates a field within which every solid inanimate object thicker than about half a centimeter is gradually hollowed out and that hollow filled with these white worm things. Preexisting hollows aren't aren't filled.
Though this effect doesn't do anything to humans, there's a secondary effect, apparently generated by the worms themselves, as it doesn't happen when no objects are affected by the field. Humans who sleep near the worms have vivid dreams of the object that generates the effect, associated with overwhelming feelings of peacefulness and comfort. After continued exposure, subjects come to the conclusion that the worms created the object, and that they wish to have its effect spread everywhere, and that this would somehow be a good thing. This isn't in an obviously mind-controlly way. Those affected just feel that the worms will eventually succeed, and that, based on their own experiences with the worm-dreams, they bring peace. Subjects may also eventually be able to create another instance of the object, but I'm not sure about that. I'd still like some way for this to affect a larger area than just where you take one object.
The worms are sort of extradimensional invaders using a rather odd invasion mechanism. They don't seek to harm us, just to use us to spread the objects so they may colonize our world.
Does this seem to scattered? Is this interesting? Should I take this further?