I was in my twenties before I realized Endora was a play on "The Witch of Endor." Since the character implies that she's over a thousand years old, she might be the original.

The first season is available through Hulu, and it's still free. *G*

I think Samantha is a pretty strong role, too. Especially in later seasons, she was willing to stand up to Darrin or even his boss if she felt she needed to.