Hippo

I only got an hour's sleep last night; appalling, but luckily it doesn't happen that often.
Paul, the sax player, has a huge browny-orange plastic hippo at his house. It's completely incongruous, and I asked him about it.
Apparently, he used to work with an exceptionally moody and bad tempered man, who could ruin everybody's day within five minutes of entering the office.
So he bought the hippo; if the hippo was facing to the right, everybody in the office knew that moodyandbadtempered was behaving true to form- don't bother asking any favours. If the hippo was facing to the left, moodyandbadtempered was in a rare sunny mood, and it was worth communicating with him.
Everybody in the office knew about the hippo's secret signals apart fom moodyandbadtempered, who picked it up one day, looked at it in puzzlement, and put it back down again- facing the same way.