Umm... I give up on the second version!!! Are you sure it's solvable?


Okay, here is my favorite:

There are two rooms next to each other: one with three switches, the other with three light bulbs. Each one of these switches turns on/off one corresponding light bulb in the other room. You can come in to each room only once, manipulating/observing the switches and light bulbs. How do you determine which switch is connected to which light bulb?