Speak with Barnaby Fletcher to learn more about Portal Shards.
Before we enter into a business relationship, I am required by the terms of my rehabilitation program to inform you that I am a recovering potion addict.
There, now that THAT's out of the way, let's talk portals!
You see, the big portals in the cities - the ones running all day and night - leak tons of magical energy. It crystallizes around the edges and is generally regarded as trash.
But I noticed during my, uh... hiatus in the sewers of Dalaran, that these shards still had power.