I remember when the game first launched, there used to be a way to fly to a Borg Unicomplex and fight them on their own turf. I remember that the objective was to disable certain nodes and such while fighting off cubes and spheres. Part of the difficulty that I always remembered was that it was often one ship vs. at least 2 cubes and 2 spheres at any given area of the map, and they weren't afraid to use a tractor beam on you the first chance they had.
They've obviously been taken out since then, but whatever happened to it?
"My frozen dairy-based confectionery attracts all the males of the species to the facilities. They all agree on it's superiority. Indeed, it is superior to yours. I could teach you the finer details but that would require monetary recompense on your part." -The Milkshake Song: Vulcan Edition