Day 01 - A show that should have never been canceled:
Typical answer, I know - but it had great potential and an excellent cast. I also absolutely adored Jayne, and not just because I'm a sucker for dudes with girly names. It's because I also really like people with hidden arsenals.
Now, who knows what would have happened had it not been cancelled, maybe I would have lost interest (I often do with one-hour shows.) Plus, besides the "Grr Arrg!" at the end of his shows, I never actually liked any of Whedon's stuff. The exception being Doctor Horrible's Sing-Along Blog..and Firefly.