Well, here is one which intrigues me sometimes: Is Atheism a religion? Personally, it is an easy one. “No” is the only answer I would ever come up with.
Things get a bit more complicated when Theist X says things like “the dictionary defines Atheist as some one who does not believe in God, this is in itself a belief, therefore Atheism is a religion.” On lots of questionnaires which ask for religion “Atheist” is included as an option, some don’t even have “none” as a choice.
Now, to me this is nonsense but I can (grudgingly) see some reasoning in the chain of logic and wondered what others think. Personally, I like the variations on the quote “Saying Atheism is a religion is like saying not collecting stamps is a hobby.”