For all you Mac OS X laptop owners out there, there's a new version of uControl out for 10.3.8 since the old version got broken by the update.
While you're evaluating your trackpad-remapping needs, you might also want to look at unnamed utility that doesn't require a modifier key to be pressed. You use two fingers to horizontally or vertically scroll and you can even do an iPod scroll wheel motion to move up and down the page. It's an interesting idea and the execution is pretty nice once you unlearn the modifier key muscle memory.
uControl is still necessary, though, because it's got a lot of other great features that this quick hack lacks.