the thing about mixing different genres is ages old.
may I quote Polonius from Hamlet, Act II, scene 2
“The best actors in the world, either for Tragedy, Comedy, History, Pastoral, Pastoral-Comical, Historical-Pastoral: Tragical-Historical: Tragical-Comical-Historical-Pastoral: Scene individable, or Poem unlimited …”
DON’T CROSS THE GENRES!!! 
Were it not for Dr Igon’s nifty gadgets I’d place GB differently, but since there is a bit of futuristic science involved, ok, I vote YES…but barely, man.
It wouldn’t be wrong to call it sci-fi, but if asked what genre ghostbusters is I would say comedy. This thread reminds me that I must rewatch ghostbusters, I picked up both movies on DVD ages ago for around £4, absolute bargain.
I’m all for nifty gadgets but it’s the paranormal that puts it in another class for me.
Comedy, absolutely. So it brings up another point. Is Galaxy Quest Sci-fi? I mean sure there’s space and aliens but the whole concept of an alien race mimicing a TV show…nope answered my own question, that could happen 
GASP!!!
Buffy IS sci fi!!! Such blaspemous talk will NOT be tolerated. That comment hurt so bad.
Now, I LOVE Buffy. LOVE IT. All seven seasons of DVDs reside on my media shelf in a place of highest honor. But I’ve never considered it sci-fi. Fantasy, Supernatural, of course.
Can you make your case for Buffy-as-Sci-Fi ? Aside from the evil nerd boys with their invisibilty gun, I mean, you’re talking one episode there ! Ok, and there was Cy-Buff, Spike’s little love-toy, which ran for awhile. But those instances were definately out of the normal circles in which the show ran.
I would also say that Buffy is not SciFi … I loved the show, I had a huge crush on Willow in high school (:o), but there’s no laser beams, no exploration of space or other final frontiers, no groundbreaking scientific/technological concepts … there’s “only” magic…
Adriana, I would love to hear your thinking on this. What in your mind pushes Buffy over into the Scifi genre?