You beat me to it. :) Some background on Command & Conquer in relation to Dune 2:

http://www.computerandvideogames.com/183584/features/command...

  "The first time we showed that game internally it had wizards
  and castles," recalls a smiling Castle. "We were working with
  Virgin at the time, and they said that they had this great IP,
  Frank Herbert's Dune, and Brett loved the books. So we took
  the game we were working on and recreated it in the Dune
  universe.

  "It solved one of the fundamental problems we had with making
  an RTS, which was that we wanted to have a central resource
  that everybody was fighting over. Dune has spice, which made
  perfect sense - and it was also used when we came to the idea
  of tiberium. It became the anchor of the C&C universe...".