It's kind of hard to follow your post, but for most of those it's not so much a matter of "smart coders" as it is that the original source code was released. And the SimCity 2000 "fix" you found is almost certainly some sort of rip from the official 32-bit Windows version.
But I guess we're getting off-topic now.
I hear Psi-Ops: The Mindgate Conspiracy is fairly enjoyable – it sounds like Psychonauts crossed with some much less whimsical FPS game – though technically that's 2004.