If the electronic rodent attached to your is of an older vintage, you may not have all the latest bells and whistles, such as the all-directions scroll ball on the Apple Mighty Mouse. Stuck with a unidirectional scroll wheel, you may think you’re missing out on all that “scroll any way you want” goodness. The truth, though, is that while you can’t scroll diagonally with your mouse, you can scroll both horizontally (as well as vertically, obviously) in nearly any application.
How, you may ask? Just hold down the Shift key prior to spinning your scroll wheel, and you’ll scroll horizontally instead of vertically—down scroll moves the page to the left, and up scroll moves the page to the right. This should work in most every application; I tested the major browsers and Apple’s applications (including the Finder), and it worked in all of them. About the only program I could find where it didn’t work was jEdit, which is a programmer’s text editor written in Java—then again, not even my Mighty Mouse will horizontally scroll in jEdit. (I’m not sure if this is a jEdit issue, or a limitation with Java apps on OS X in general.)
While there are good reasons to buy a new mouse, if all you feel you’re missing is horizontal scrolling, try the Shift key before reaching for your pocketbook.