How can I enable magic mouse momentum scrolling in Windows 7? I have my magic mouse and I've gotten it working with windows 7. Left and right click work as well as scrolling.

Now I want smooth/inertial scrolling as well as middle click. Is it possible?

Also is there a way to imitate the ability in OS X to scroll any window regardless of whether or not that window has focus?
Answering the second part of the question, KatMouse is your solution.  It brings very Mac-like cursor/scroll interaction to Windows.