I finally got around to building my own Hackintosh using no special hardware really. I guess the only requirements you really need is a CPU that supports SSE2/3 instructions. Just grab the latest Kalyway DVD and you're good to go.
Mac OS X (Darwin) didn't detect my on-board NIC right away and I didn't feel like finding the kernel extensions for it; whatever so I found a spare 3Com NIC which worked. I'm stuck at 1024x768 until I get a new graphics card. I haven't tested audio yet so I'm not sure if that works. Edit: Works perfectly!
Edit: Screen shot here.
There's a shitload of other kernels you can try, but the original mach_kernel worked for me.
Anyway, it's working pretty well I might say. The Halo demo doesn't work (neither does the full game) as I get an error message on starting.
It's just nice to have that Mac style, nice shiny icons, beautiful desktop, overpriced hardware etc... :)