When it comes to meaningful questions, "How is this night different from all other nights?" certainly takes some beating. It provokes deep thought on the meanings - obvious and not so obvious - of Pesach, is an excellent opportunity to begin explaining our history and traditions to young children and has been asked every year for thousands of years, which surely shows it has something.
One other question has been occupying me this year, but unlike "How is this night..." nobody has been able to answer it. That question is:
Why don't we eat charoset all year round?