gun machine talk gets them really genki, yeah.
of all the last lessons i did, the best was Inaka Basketball. BizzQuiz (jeopardy style game) a close second.
they love basketball. downside is, you need a lot of questions. because it is very fast paced. i prepared 50questions and almost ran out.
...and u have to find a big ass garbage can PLUS u have to make a nice and big paper basketball.
put the 3 points line really far away. they always go for the 3 points and almost never hit. until one group figures that they can get more points with the easy 1 point shot. implement the "3 mistakes is 1 point"-rule, makes the game faster and more exciting since they are not so afraid to answer.
bizz quizz is less preparation, but u have to check all the questions and revise a couple, some of them are just false.
get the test question bank from the old forum
http://englipedia.proboards105.com/index.cgi?action=display&board=educational&thread=718&page=1. (watch out some minor mistakes in there, too)
also, students especially love to look for pictures in the textbook, e.g., "I see a monkey wanking. What page?" and of(f) they go.
and what gets them to work their brains at least a little is the wordscramble. try to make up fake words (or real words) out of the letters, makes it harder, eg. LOVEUNTER for "volunteer" or CAFE for "face".
i guess, without any preparation u will never have an exciting game.