1. Firefly 2. Space Above and Beyond 3. Jericho 4. Journeyman 5. The 4400 6. Terminator: The Sarah Connor Chronicles 7. Heroes 8. Dark Angel 9. Star Trek: Enterprise 10. SGU Stargate Universe SGU Stargate Universe 11. Invasion 12. V 13. Caprica 14. FlashForward 15. Dollhouse 16. Threshold 17. Terra Nova 18. The Event 19. Defying Gravity 20. Farscape Better to end an episode too soon than an episode too late. IMO all of these ran out of ideas before they ran out of episodes (with the exception of Firefly).