Probably a toss-up for me -- it's so hard to choose just one! I am a long-time trekkie, but I really enjoyed Eureka -- I want to move there! (Of course, if I had a holo-deck, I could recreate Eureka, and move in there... but having it for real would be better.)

Lost in Space was and is still my all time favorite

I always enjoyed the original Star Trek series. I could never get into show like Deep Space Nine and whatever. Plus Quantum Leap. Those were the only real SCI FI shows I watched except for an older show, 60's I believe, was the Land of the Giants. I loved that show too.

Would have to say Firefly (heard a murmour that they had thought about making a 2nd Serenity movie) and Stargate, also like Star Trek but not a big fan of the Deep space 9 series..

The BBC series "Torchwood" is my favorite sci-fi show, probably ever! I adore everything about it. Except that fact that it isn't on often enough! The BBC series are only 13 episodes, and then it's at least a year between series. Drives me crazy!

I also love the new Dr. Who, but they are only doing 5 episodes this year. Wah!

I love Smallville - I think it's great. The one show that is my fave of all time is 'Buffy the Vampire Slayer' though, I never miss an episode and me and my friends all watch the boxsets, it was fantastic and had such great female characters too.
I never got the whole Star Treck thing - I can't stand that show or the premise. I did like Tru Calling, but they cancelled it

Wow -- this could go for a while Early favorites (and I mean really early ) * Johnny Quest * Star Trek (original series) * Lost in Space (can't hardly watch them now but loved them when I was little -- when it didn't give me nightmares -- I was really little) Gone but not forgotten *Buffy *Angel *Firefly *Star Trek DS9 - for some reason I enjoyed this when no one else did -- Cisco took awhile to catch on, but Avery Brooks is an amazing actor. And I loved the romance that Warf had with Dax. It went downhill for me when Dax left. *Star Trek Next Gen *Highlander (can I slip this in) - it's sort of an all-time favorite *Roswell *Dresden - I was just getting into this when it disappeared *Farscape -- slow to catch on this one, but again, romance won me over. turned off a bit by the dark themes though Now favorites *Eureka -- knew I forgot something -- then saw someone else's list! *Doctor Who *Chuck (stretching the sci -fi tag a bit but it does have future tech and lots of lovely sci-fi references) *Heroes -- not keeping up so much anymore, but hoping to catch up *Lost -- though that's exactly where I am with Lost -- totally lost and behind -- but want to watch not so much for plot, which I wish had stuck with "a bunch of people stuck on an island with a scary monster" -- but for characters -- they bring out the darndest surprises and have really some of the best in-depth characters on television know there must be more I'm missing

i don't get scifi in my area; so i'll just list my favourite science fiction shows: star trek os star trek tng the outer limits twilight zone all Star Gate franchises (SG, SG-1, Atlantis, etc.) Andromeda prob others also :grin:.

True Blood has gone screeching to the top of my list, followed by Heroes and then Dollhouse (which they've now cancelled )

The Outer Limits (original series)
The Prisoner
Star Trek (original series and the next generation)

There have not been that many great SF tv series.
Good SF is hard to find on TV.