There are some really cool questions out there. Questions that do not require a lot to ask and do not require a lot to answer. Here is one such question (I can't remember where I first found this question or something like it):
Suppose you put take two identical cans of soda out of the fridge and place them on the floor in the middle of a room. One can you leave alone and one can you cover with a wool blanket. After an hour, you come back and check on the two cans of soda. Which will be warmer?
First, why do I like this question? Mainly because everyone can give an answer. If asked about the ground state energy in an infinite square well, I would get a lot of "dunno". Second, I like this because it looks at an interesting idea - what does the blanket actually do?
Ask your friends this question, it's fun. Or, if you are not sure of the answer, try it out.