2 PCs connected to a Quad HD array suggestions.

I know theres the options of Nas server Quad arrays,but is there cheaper options ?

The situation is like this there are 2 PCs one belonging to me the other my brother, my PC is used for all the downloading & storage of music/films ect due to the large capacity of hard drives I have, but if my brother wants something he comes in and switchs my PC on or just asks if he can borrow it for a minute while Im using it so that he can get access for whats on my hard drives,

So the Question is this, is there a way he can have his PC also connected to my hard drives with or without my PC been switch on, so basically 2 PCs more or less sharing the same Hard drives (the ones used for mass storage only).

Also just to mention there is only a wall between the 2 PCs as each one is in its own room, so if you imagine the PCs are like back to back of each other with only the wall between them, so putting a Hole in the wall so that a cable can be thread through is ok.

Hmm, as I thought, I did hope there would be another way, instead of paying out
$/£200+ for a NAS, but still I will give more thought to this, or I will have to adapt.

Use the NAS as a backup for your main machine. Your bro can then read from it, but you are not affected by its performance in regular use.