Don't go for the regular Z, get this!:
Oh yeah, and dweez, it IS a rotary in the RX-8. It is supposed to be built a little bit different to make it both more powerful and reliable.
If you go to the ATI link that Dweez posted, at the bottom there is a screensaver of MC Escher's famous "Ants" which is a Moebius Strip with ants in 3D. It looked super sweet, but my cool GF2 won't support either the screensaver or Pipe Dreams.