Could I? or Couldn't I?

"I couldn't care less" or "I could care less"? I've always said "I couldn't care less" but I never heard anyone else saying it. Other people always seemed to say "I could care less" (correct me if I'm wrong and you, The Reader are normal like me).

Anyway, I just wanted to see whether I'm way off base so today I found an awesome website to answer this question and others like it.

By the way, the answer according to Grammar (whoever that may be) is:
"Although it makes absolutely no sense, these two expressions mean the same thing. The "I could care less" version came about in the United States, in the 1960s, but it has become widespread in spite of its lack of logic."