GamersGate has a ton of spacey game deals, including:
- Master of Orion for $1.48, Master of Orion II for $2 and a double pack for $2.98.
- Even though it was awful, they also have Master of Orion 3 for $4.98.
- Really Big Sky for $8.99
- Evochron Renegades, Evochron Legends for $13.97, Evochron Mercenary for $17.47 and an Evochron Complete Pack for $31.49
- Sword of the Stars by itself for $3, Sword of the Stars: A Murder of Crows for $4.50, Sword of the Stars: Argos Naval Yard for $1.49, Sword of the Stars: Born of Blood and Sword of the Stars Complete for $5.99
- Sword of the Stars II: Lords of Winter for $9
- Arvoch Conflict for $6.97 and Avroch Alliance for $13.97
- Genesis Rising for $1.49
- Space Rangers for $3.40, Space Rangers 2 by itself for $3.40, Space Rangers 2: Reboot for $3.40 and Space Ranger Complete for $10.20.
- Darkstar One for $2.50
- Lost Empire for $2.50 and Lost Empire: Immortals for $2.49
- SpaceForge Rogue Universe for $1.49
- The Tomorrow War for $6.80
- Dark Horizon for $2.99
- Star Assault for $2.49
For my money, the best deals there are for Master of Orion II, Sword of the Stars Complete and Space Rangers 2: Reboot, but many of those are great games. Enjoy!!