Dune 2 was great, as was Warcraft (didn't they use the same engine?) I remember being horribly addicted to dune2 on my old 486dx brick of a laptop (which at the time i thought was the mutts-nuts :)
It was definitely possible to complete the game as all 3 armies (just required plenty of save-loads :P
It was definitely possible to complete the game as all 3 armies (just required plenty of save-loads :P