If you take a gaming mouse and set its customisable buttons to things like copy, paste, delete, "next tab" or a window-switcher, you can seriously upgrade your own work-time productivity by allowing yourself to get more done with every click.
Photo via nSeika.
As Unplggd argues, gaming mice aren't just for gaming: they can be put to use outside the battle zone, too. A gaming mouse usually has better tracking (which makes for smoother cursor movement) and several customisable buttons, so why not take all that and apply it to regular computer work? Hit the link for some thoughts on useful shortcuts to assign to your mouse.