I detest the fact that the browser uses the F-keys for its own shortcuts. We have an a web-app ported from a mainframe app that uses the F-keys for functions the _user_ carries out and users love being able to press F1 through F12 to activate buttons and other page elements. Familiar users can navigate throughout a complex app without the mouse and without continuous, repetitive tabbing.<p>Overriding the browser should absolutely be allowed.