Wormhole
Wormholes are rips in time and space that allow quick travel from one part of the universe to another in a short amount of time. They are used by everyone at some point whether it is to deliver goods to complete an auction. If you use the wormholes wisely you can cut a journey down from 50 parsecs to one that is only 7 parsecs. Also they can be used to travel to your enemies or even escape. There is a danger to using the wormholes however they can close at any time so you have to be extra careful when using them or you could get trapped on the other side of the universe.
Several empires attempt to map the wormholes every week allowing them to gain the advatage over their enemies in war and competitors in trade. But they have their work cut out as 50% of the wormholes reset every friday and so they have to start their work all over again each week. But for them the gains outweigh the costs.