This really is fun: I installed SPORE on my Mac and there is no copy protection whatsoever. I don't even have to keep the disk in the drive to play it.
When will these distribution idiots (RIAA, game companies, et al.) realize that DRM just plain doesn't work? There's no way to stop piracy of digital content, so just work with that limitation, instead of fighting an impossible battle that only punishes legitimate customers.
I can't find the quote, but I believe it was Neils Bohr, who when asked how supporters of quantum physics overcame the resistance by classical physicists, said "we didn't, we just waited for them to die." I believe the same principle applies here.
With RSA encryption in the CPU, you can definitely enforce DRM. Just decrypt the game's code on the fly in a DRM-enabled CPU. The only way to break the code is to get the RSA key, or spend year(s) hacking the key.
Only one person has to hack the key. Then he/she can distribute either the key or the decrypted content to everyone else. This is exactly why DRM will never work.
Have you noticed that XBox 360 is not cracked (short of one batch that had leaky DVD drives)?
It's not a problem to create a real pain in the ass for the pirates. The problem is to avoid creating real pain in the ass for normal users and your own developers at the same time.