Acceleration - I use Crazy Taxi to teach acceleration.  Students watch the game in action and then write specific examples of when there was a change in speed or direction.  I often play the pod racer sequence from the DVD : Star Wars I - The Phantom Menace to intoduce acceleration and velocity.

Simple Machines -  We play 4 player hockey (and 4 player tennis on the Wii) and I have students study a textbook diagram of Class 1, Class 2, and Class 3 Levers. Students are to find 5 examples of levers and then they work in groups to classify the levers according to their classfication.  Do the levers change direction, increase distance, or increase force?

How to write a lab procedure - I use Sonic Adventure 2 to have students learn to write a lab procedure.  I have some volunteers work their way through the first level of the game (Escape from the City).  Once students have seen the level once or twice, they begin to take "field notes" where they write down notes about how to beat the level.  After a few more turns, students write a detailed procedure about how to complete the first level.  There is also a kart race feature on this game that allows students to race cars based on their level of speed and acceleration. This is a great way to help students differentiate between speed and acceleration because there is strategy involved.  Do you want a car that has a great top speed (but can't get there too quickly), or do you want a car that can get to its top speed quickly (but the top speed isn't too high).