Wing Commander 3
During play, enter Alt+O at the same time and get Cheat Options menu.
When starting WC3, exit from windows to MS-DOS, then go to your CD-Rom drive, and type "WC3- Mitchell" and press return. During the game, press Ctrl+W to destroy your current locked target, or Ctrl+Alt+W.
Thanks to Revolution reader Henning "Coolspot" Thornblad, C.Wales, and Paul Raftery!