Yup, definitely Buffy. I also love all of the Companions on Nu!Who, which I think puts me in the minority (even if I think the writing for all of them isn't equally strong, I like them all). I like Uhura on nu!Trek (she's very polarizing). I like all of the women on Mad Men--there's a lot of Betty hate, but I think she's interesting and oftentimes sympathetic, if deeply flawed. I like Michelle on Skins, who isn't generally well-liked.

Of course, then I also like the characters everyone else loves--I'm now very fond of Scully and Aeryn Sun, for instance.