Possible to get a transcript?  

One of my favorites for something guarded by a mage.

A door that has a picture of a person, face, ECT that can talk, and a door handle. The door does one of two things:

Calls Itself all-knowing, boasting of its intelligence. It then asks the party for a riddle it can't solve. No matter the riddle, the door will answer no matter correct or incorrectly, and proclaim itself right. The correct answer would be to compliment the door, it then lets the party through. Example: Monk: "I have a head and a tail, but no body. What am I?" Door: "A snake." Monk: "No! it's a coin." Door: "No, I am correct. I am all-knowing." Wizard: "Of course, there's no way we could give you a riddle you can't solve. You're just too smart. Door: You may enter."

Or, it loudly interrupts the person trying to open the door, prolonging them to open it. The ultimate answer is to just open the door. It's not locked, the door is just there as a distraction.

I made one last session in my GREYHAWK campaign to enter a shrine of Boccob, in the form if an eldritch control panel with 8  Colors if Magic. While it was relatively simple, it took them some time to figure it out.

Before that i made a dwarven sudoku inspired puzzle, replacing numbers with runes.