The ones of you who ever tried a Linux distribution will have noticed the scrolling behavior on the system. While in Windows you can only scroll the active Window, even if your cursor is nowhere near it, in Linux you always scroll the Window that is right beneath the cursor which is far more intuitive and useful, at least to me.
Eduard Hiti on http://ehiti.de/katmouse/ hast developped KatMouse, which provides you with exactly that feature and some more, which you can choose to disable if you don't need them (includes pushing windows to the back of the screen and custom functionality for special applications).
Download KatMouse here and install it. If you didn't put a shortcut to the Startup folder during installation you can find the folder in "C:\ProgramData\Microsoft\Windows\Start Menu\Programs\Startup" - just drop a Shortcut in there and KatMouse will start when your system starts up.
To edit settings, just right-click the tray icon and browse through the tabs. Find more information on the linked homepage!