Revenant Supercarrier in EVE Online. Darn near impossible, in fact. The ship is worth around 300 billion ISK, coming out to about $8,000 in real currency. The ship is so potent that up until last night, there were thought to be no more than three in the entire game. As of last night, there were two. One of the Revenants was destroyed in a battle between Habitual Euthanasia and Black Legion.
Habitual Euthanasia apparently responded to a call for help, fielding the carrier against Black Legion, leading to its destruction. Speculation about whether this was a trap to destroy something valuable or simply a lucky break for the opposing side is being flung around with no conclusive answers. The video recording the destruction is embedded after the cut, although it's zoomed out enough that you cannot enjoy a slow-motion replay of one of the rarest ships in EVE Online going up in flames like a cheap firecracker.