"Performance per dollar" is a strange qualifier for a laptop. If you want something small, portable, and powerful, maybe one of those Mac Pro cylinders might suit you when they come out. If you don't (much) care about portability at all, just build something in a mini-ITX case with a handle, and throw it in the boot of your car.

The point of a laptop is good, light, sturdy industrial design, long battery life, and quality interaction features (solid keyboard, responsive touchpad, good webcam, flat SPL curve on speakers, etc.), while optimizing performance given that. That's what you're paying the Apple premium for, not the OS. Those qualities remain when you run Windows on the hardware.