I might have posted to a similar thread like this a long, long, time ago. . . so I hope I am at least a little consistent with that if I did.
Past Favorites:
1978 Battlestar Galactica
Firefly
X-Files
Current:
Naruto (including Shippuden)
Eureka
Stargate Atlantis (?)
Close runner ups for Anime include Cowboy Bebop and Evangelion.
Close runner ups for Sci-Fi are the new BSG and Star Trek: The Next Generation.
--Ethan