A story about the recently departed gadol she-bigdolim Rav Avraham Genechovski ztz"l: His mind was a little bit in the clouds. He was constantly immersed in Torah and Avodas Hashem so simple earthly matters were sometimes neglected.
He used to buy ice cream for the boys who would help him. One time the boy wasn't there so he placed the ice cream he had bought in the closet.
When he returned some time later all that was left was a puddle. He looked at it and said: "I have 2 questions. One, where is the ice cream I bought? Two, how did this puddle get here?"
He clearly knew the answer to both questions but by asking he amused the boys who were there, so why not...:-)