It came as a mild surprise to me when I woke up today and found that developer Alessandro Levi Montalcini had released an update to his popular USB Overdrive driver and configuration utility. I have been using this for years to customize my mice and other input devices, and while there have been small bug fixes to the previous version released, the driver has been pretty much unchanged for years and the USB Overdrive website has been forever claiming a new release was in the works.
When Apple started releasing computers with USB ports, there were not many input devices for the Mac that supported the new technology. However, even when they did start coming around, many times vendors did not include generic drivers in the devices that would enable them to function seamlessly on Macs. Instead, people still had to find drivers from vendors to get their mice, trackballs, and joysticks working.
Additionally, the classic Mac OS did not have support for more than one button on input devices, which was a hinderance when trying to get plug and play functionality out of multi-button USB devices.
One of the ways to overcome these initial USB shortcomings was to use the utility "USB Overdrive", which was a highly customizable generic input device driver that allowed for all buttons on input devices to be used for many user-specified options, including built-in functions such as page-down and application switching, or even providing custom keystrokes to applications with modifier keys. This along with application-specific profiles for buttons, mouse speed, and mouse acceleration settings allowed for the customization of USB devices between games and other applications on the system.
USB Overdrive made its way to OS X, preserving its usefulness in the new OS and allowing for most input devices to be used and customized in the system when manufacturers did not provide adequate drivers (if at all). While it has been updated with small bug fixes here and there, it has remained relatively unchanged for years.
Version 3.0 of the driver has just been released, adding adding new features, refinements, and a new interface. If you have not used USB Overdrive and are interested in highly customizing your mouse or other input devices, and wish to do so on a per-application basis, then you might want to check out USB Overdrive. Up to now the previous version has run quite well on all versions of OS X (Including Snow Leopard), but the latest release better integrates it into OS X and provides 64-bit support for Snow Leopard.
The latest version is $20 shareware, and requires at least OS X version 10.4. Alessandro Montalcini has made a note on his web page that the new version does have a few device-specific bugs which will be addressed soon, but these are only for a few devices that have non-compliant button configurations. Check it out at the developer's page here: http://www.usboverdrive.com
(USBOverdrive Icon Credit: USBOverdrive/Alessandro Levi Montalcini