Brain Threes
Atop Knowhere is a crater with a brick locker, and three power lines.
Activate the console at the end of each line to free the brick. These are all code-combo consoles, so watch for the arrows, and input them in order.
One console is in an indentation toward the Citadel-side of Knowhere. This is also right by the finish line of an aerial race from Attilan, if you want to do that first.
One is in an indentation on the Nueva York side of Knowhere.
The last is near the top of Knowhere's spine, inside the spinal column.
Activate all three, then return to the topside crater for your brick.
