In short: No.
In long: Yes. IF you're willing to build a PC with parts that Apple actually have drivers for. Which isn't much, but it's still, theoretically, do-able.
There are hacks around on torrents, but they're illegal, and just hacks, so they're nothing like the full O/S.
It's because Apple own the hardware pool they use, and as such, they only have a small pool they need to write drivers for, and as it isn't cost effective for other firms to write Apple drivers, they don't. So Apples' "It just works" slogan works because they choke the hardware down to a small elite. When you come to look at OSX as just an OS it becomes a lot more restricting, as it can only be used for the hardware Apple own.
So in a way, it makes Microsoft look like nice guys.