Type the following codes into the in game chat box. 
They should also work in the demo: 

forcefood - 1000 food 
forcenova -1000 nova 
forcecarbon -1000 carbon 
forceore - 1000 ore 
forcewood - 1000 food 
forcebuild - Build buildings and units instantly 
forcesight - No fog 
forceexplore - Reveal Map 
forcebuild - Instant construction and research 
luke skywalker - Win mission 
skywalker - Win mission 
simonsays - Get Simon the killer Ewok 
tarkin - Destroy all enemies 
darkside8 - Kill Opponent 8 
darkside7 - Kill Opponent 7 
darkside6 - Kill Opponent 6 
darkside5 - Kill Opponent 5 
darkside4 - Kill Opponent 4 
darkside3 - Kill Opponent 3 
darkside2 - Kill Opponent 2 
darkside1 - Kill Opponent 1 
scaryneighbor - Speed boat with increased fire power; screen 
must be over water when activated 

forceboat - Press [Comma] for invisible naval ship; screen 
must be over water when activated