Numb3rs is probably the only show I watched from the beginning. I saw the premiere and just fell in love with it. It feels so different from every other crime drama out there. The best way I can put it is that while all the other dramas feel like uptight, Numb3rs just sat back and relaxed. It never felt too too serious (unless it needed to be), and was never guilty of being overly dramatic. The dialogue just felt natural, and it seemed like all the actors had good chemistry with each other (except for Nikki, she was just never convincing to me). I was sad to see this show end, but honestly it didn't have much left to cover.
But anyway, a wonderfully unique (and educating) show with great characters, and entertaining stories.