Windows

it's not legal i think

it's possible

so only 1 win goes with one pc and that is it ?

depends on your windows version.. if you have a retail version of windows xp you may install it on 3 pc's i think. if you have the OEM version you may only install it on the pc it came with, but it worked for me anyway so i guess you could try

i think my windows is on 8429837423 Pc's installed^^ so ofc its possible

It's possible and you won't have any local network problems.

Its pretty easy, windows update will try to do an authentification when you add Service Pack 1, all you do is google some anti auth system (its a java based code i think) that you input into your address bar at the top.

At least thats what I did a few years ago, system may have changed by now.

cheeers guys