Their are illegal cracks to be found floating around on the internet. I don't know PC Advisors standpoint on these IF you own the original disc. I personally do use such cracks, because having to keep swopping discs etc becomes tiresome "BUT ONLY IF YOU HAVE THE ORIGINAL GAME". If you have access to P2P software, like Emule search for something "game name" and no cd and this should list such a crack
I believe their is some program which creates exe files so you don't have to use the CD because I once came accross it on a CD Mag.