Star Trek Online's Delta Quadrant, the USS Voyager comes across a mysterious object. The ship's crew immediately brings it aboard and tries to figure out what in the world it's supposed to be, coming to a lot of conclusions about what it isn't while being unable to find many answers beyond "it's probably a communication device of some kind." It also doesn't quite match any of the technology seen from the obvious sources of technologically enhanced mystery objects like the Solanae Dyson Sphere.
And yet everyone thinks keeping this on a ship is a good idea? There are a lot of episodes arguing against that.
All joking aside, there's a fair bit of lore to be found in the latest official dispatch from Star Trek Online, hinting rather solidly toward potential new encounters for players in the future. What it all means remains to be seen, but you can take a look at the lore and puzzle over what Voyager found.