Press enter to pull up the entry console, then type any of the following cheats:

$BUILD X: Build speed set to X
$COLLISIONS OFF: Asteroid Collision off
$COLLISIONS ON: Asteroid Collision on
$FOGOWAR OFF: Fog of War OFF
$FOGOWAR ON: Fog of War ON
$FPS OFF: Frame Rate off
$FPS ON: Frame rate on
$GET ALL TECHS: All tech researched
$GET TECH: All tech researched
$GOD OFF: God Mode off for selected unit
$GOD ON: God Mode for selected unit
$RESEARCH X: Research speed set to X
$RU #: Get # of Resource
$SU #: Get # Support Units
$WEAKEN ENEMY: Weaken Enemy Hulls
$WIN: Mission Won