Wing Commander 3

Startup the game with
wc3 -mitchell
Then, during flight:
[Ctrl]+[W] : Destroy current target
[Ctrl]+[Alt]+[W] : Destroy all enemies in area

-- To view all the movies:
With <Caps Lock> on, hold [Shift]+[Delete]+[F10] and
type LORDBRITISH

-- Easter egg:
Put one of the CDs 2-4 (not 1) into the drive and go
to the screen just before you load things. Click on
the stars in the following order: double click on
the upper right, lower left, upper left, lower right.

-- The documented one:
Press [Alt]+[O] during play for a cheat menu. (Information from Cheat Machine)