According to GameCopyWorld, OpFlash uses Safedisc and X2 uses SecurROM (Gothic3 said TAGES).
FADE was an exclusive Codemasters thing that died a while ago so I don't think it's listed anywhere as official copy protection. But it was troublesome nonetheless. I remember using a crack that didn't completely wipe out FADE in OPF which resulted in my weapon accuracy decreasing to about 5%. As for finding and disabling all the triggers in the code, I don't think you actually have to play the game to find them. Though, you do have to play through to test your fixes which is why games with TAGES sometimes have multiple cracks.
I find the following quote about FADE rather humorous:
"The beauty of this is that the degrading copy becomes a sales promotion tool. People go out and buy an original version," claims Bruce Everiss of Codemasters.
Yes, because when people play games that appear to be buggy, they immediately go out and buy them.
This is why FADE is dead.
This comment was edited on Apr 22, 14:19.