maybe there's a forum there too that likes to discuss these issues
There are a whole lot of them, actually.
But here it is, in a nutshell...
Mac OS X is designed to work ONLY with the hardware found in computers built by Apple. Almost all PCs have some amount of hardware in them that is not found in any Macintosh. This can be video, sound, networking, drive controllers, basically anything you can think of. There isn't just one universal set of hardware found in all Macs and PCs, and now that Mac OS X runs on Intel processors it doesn't mean it will happily run on any PC you may have lying around.
Installing Mac OS X on a PC requires you first to spend a huge amount of time just getting the damn thing to boot and install. Afterwards, you have to spend hours and hours hunting down drivers and hacking away at different bits of the system trying to figure out why some obscure piece of hardware you have isn't working at all. In most cases, you'll never ever find a solution, and will have to settle for a PC that is only partially working. Next, every time a software update comes, you have to wait around for a hacked version that will not break everything, or hack it yourself. Any time you apply any updates or install new software, you have to pray to god that your system boots up again. And Mac OS X on a PC seems to have a markedly higher frequency of kernel panics, random freezes, and beech balls than an authentic Mac.
So in conclusion, not only is it against the EULA, against MacRumors, and morally unsavory, it is also a tremendous amount of constant effort that never results in 100% satisfactory mac-like operation. It is completely not worth it at all.
If that isn't good enough for you, then you really aught to go to Google.