fromGoogle -
// transmogrify a user-entered Q into an F (Gecko browsers)
if (String.fromCharCode(event.charCode) == "Q") {
var newEvent = document.createEvent("KeyEvents")
newEvent.initKeyEvent("keypress", true, true, document.defaultView,
event.ctrlKey, event.altKey, event.shiftKey,
event.metaKey, 0, "F".charCodeAt(0))
event.preventDefault()
event.target.dispatchEvent(newEvent)
}
Дома попробую...