From a small briefcase, remove a clear plastic stand with a single hotel room key hanging on it. The hanging key remains in full view throughout the routine. The audience will try and guess your hotel room number. Ask the audience to name any number from 1 to 100. They can change their minds as many times as they wish, so you know it's totally random. It really is. Take your clipboard from the briefcase and write the freely selected number on a large sheet of paper. Remove the key from the stand. Remember, it has been in full view throughout. Turn the tag around. On the back is the room number. The very same number the audience randomly selected. You can perform this illusion with a different outcome every time.