Smart Scroll - Smart Scroll makes scrolling smoother, faster and more comfortable:
Smooze - Smooze animates your scroll and adds functionality to your non-Apple mouse (scroll-wheel mouse).
Scroll Reverser - Scroll Reverser is a free app for Mac OS X Snow Leopard and Leopard that reverses the direction of...
ScrollNavigator - ScrollNavigator helps you to scroll your documents horizontally and vertically. Simply click and hold down the right (or the middle) mouse button anywhere in a window and move the mouse to scroll the window contents.
Mac Mouse Fix - A simple way to make your 3rd party mouse better.
SmoothScroll - Gives smooth scrolling and Shift+Wheel horizontal scrolling in almost all applications.