uControl gives you the ability to take those useless keys, that you're certain would have been better fashioned as something else, and turn them into something useful. It started out as a simple hack to remap the caps lock key to a control key but has since evolved into a fairly sophisticated means of not only remapping modifier keys, but gives your trackpad a virtual scroll wheel, or gives lefties a sensible mouse, or gives people with disabilities the ability to type with one hand. Note: the one-handed typing ability has been removed due to possible patent infringement.
What's new in uControl
Version 1.4.6: Release notes were unavailable when this listing was updated.