There are many things I enjoy in this life, but one of the things I enjoy most is being horrible to my kids, in an underhand way.
Most of my classes know now that there's little to be gained by yelling "game, game, game!" enthusiastically at me. This is because if they I write the word "game" on the board and tell them that if they say it five times then there'll definitely be no game.
It's pretty academic, because I hardly ever give them a game anyway. And if I do, it last for about 20 seconds before the bell goes, and is as dry as dust.
I also now bring a small clock into class with me. This clock is set 4 minutes slow. This is because I sometimes promise them that if they work then they'll get a game (the fact that my games are less fun than work doesn't seem to deter them) in the last 5 minutes of class. Of course, what they don't know is that as well as manipulating them, I'm also manipulating time. So, if they have worked quite hard and I do tell them "Books way - game!" then they have about one minute to put their books away and prepare for the excitement of a game before the bell goes. My poor kids never seem to twig that all the odds are very heavily stacked against them for getting a game.
And believe, right now there is little that gives me more satisfaction than saying "Books away - game!" before the bell goes and I say well, "Oh well, better work harder next time."