From Antibody Software:
WizMouse causes your mouse wheel to scroll the window under the mouse pointer instead of the currently focused window. You don't have to click on a window to focus it before you're able to scroll it with the mouse wheel. It can optionally enable mouse wheel functionality in applications that do not support mouse wheels. It can also optionally reverse the mouse scroll wheel direction to simulate "Natural" scrolling as on Apple's OS X Lion.
What's new in this version:
Version 126.96.36.199 adds optional reversed mouse wheel scrolling - like OS X "Natural" scrolling. Fixes a bug where WizMouse might terminate after a few days when running on Windows Vista/7 if "run as administrator" was enabled.