Every MacBook, MacBook Pro, and MacBook Air have hardware included called the Sudden Motion Sensor (SMS.) Sudden Motion Sensor is motion-based hardware and data-protection system. The accelerometer detects sudden acceleration, such as when the computer is dropped, and prepares the relatively fragile hard disk drive mechanism for impact, preventing data loss and drive damage from a disk head crash. When the computer is stable, the drive operates normally again. A clicking noise can be heard when the sudden motion sensor kicks in if you move your computer up and down.

The motion sensor can also be read by programs running on the MacBooks and a number of programs exist that use the motion sensor to make the computer tilt-aware. This way, tilting can be used as a human interface device. For example, tilting can be used for scrolling or for controlling games.

Here are some games and apps that target Sudden Motion Sensor:

AMS2HID- An application that translates orientation data retrieved from the Sudden Motion Sensor into input data for a keyboard or a mouse. Use this to enable Sudden Motion Sensor for games and apps.

To use AMS2HID for a game (I'll use Neverball as an example):

-Open AMS2HID
-Set it to Normal Mode and set the HID to Mouse
-Open Neverball
-Go back to AMS2HID and select the application as Neverball
-Go back to Neverball
-You should now be able to control the tilt of the floor by tilting your MacBook

Download from SMSRotateD

Bubblegym- The first tilt-sensitive game for notebook computers. Use the SMS to control the directions of the colorful marbles and collect the fruit by tilting your MacBook up, down, left, or right.

Note: No AMS2HID necessary to activate the SMS controlling.

Download from Bubblegym

LiquidMac- An app that mimics the behavior of liquid by creating a particle system that reacts to the computer's orientation. Use the SMS to control the speed and the placement of the liquid on the screen.

Note: No AMS2HID necessary to activate the SMS controlling.

Download from Oriol Ferrer Mesią - LiquidMac

MacSaber- An app that uses the SMS to detects the speed of movements. As you move your laptop, MacSaber plays varying levels of Light Saber sound effects, from a waving sound to exciting saber crashes.

Note: No AMS2HID necessary to activate the SMS controlling.

Download from Download MacSaber for Mac - Uses Mac laptop sudden motion sensor, makes lightsaber sounds. MacUpdate.com

Neverball- A game that uses the SMS to tilt the floor. Roll a ball through an obstacle course before time runs out. A step-by-step guide under AMS2HID shows how to activate the SMS controlling with Neverball.

Download from Neverball - Download

Neverputt- A game that uses the SMS to aim the ball before trying to hit it into the hole. It's a multiplayer miniature golf game, built on the physics and graphics engine of Neverball. Use the same technique described with Neverball and AMS2HID to activate the SMS controlling.

Note: The Neverball DMG you will download has a "Install Neverball" installer that includes Neverputt.

Download from Neverball - Download

SMSRotateD- An app that triggers screen rotation based on the orientation data it retrieves from the SMS. It uses the SMS to detect if the notebook has been physically rotated to the point where the display's orientation has changed from landscape to portrait, or vice-versa. When such a change occurs, SMSRotateD triggers an appropriate rotation of the displayed screen.

Note: After launching SMSRotateD, the "Start" button within the application's window must be pressed to enable SMS-based screen orientation. When "Start" is pressed, the notebook's base should be parallel to the ground, to allow SMSRotateD to establish a "level" state. Afterwards, the button becomes the "Stop" button. As a convenience and safeguard, the escape key toggles between the two states of the button. Disabling SMS-based screen orientation (that is, going to the "Stop" state, whether by pressing "Stop" or by hitting escape) resets the screen to its original, non-rotated state. Quitting the SMSRotateD application also resets the screen.

On some notebooks, you might need to check one, or even both, of the axis flipping checkboxes. For example, if physically rotating the notebook 90 degrees clockwise causes the screen to rotate anti-clockwise, checking the "Flip x-axis" box will rectify this behavior.

Another important point to note is that SMSRotateD does not alter the user-facing orientation of the built-in trackpad. In other words, even though the screen has been rotated, say, by 90 degrees, the trackpad logically remains in its original position.

Note 2: No AMS2HID necessary to activate the SMS controlling.

Download from SMSRotateD

Skip Checker- An app that lets you use the SMS in different ways such as:

-Skip to the next tune by slapping your MacBook.

Note: Please be careful when slapping your MacBook. MacBooks do not deserve abuse and there is only a small necessary force needed for this to work. Find the lightest possible touch that Skip Checker will respond to in order to prevent unwittingly abusing your MacBook.

-Run AppleScripts or play sounds by moving the computer around
-Using your computer as a musical instrument
-Some 3D fun

Note 2: No AMS2HID necessary to activate the SMS controlling.

Download from Download Skip Checker for Mac - Fun with your MacBook Sudden Motion sensor. MacUpdate.com

Tilt Mania- A game that uses the SMS to tilt the level in order for the ball to progressively move down through slots in the floor levels.

Note: No AMS2HID necessary to activate the SMS controlling.

Download from WXS.ca: Tilt Mania

Tilt Scream Pong- A game that uses the SMS to play Pong. Tilt the laptop to control the paddle and scream to increase the size of the paddle.

Note: Please do not hurt your voice by screaming too loud. Find the softest voice level Tilt Scream Pong will respond to in order to prevent losing your voice.

Note 2: No AMS2HID necessary to activate the SMS controlling.

Download from Future Feeder » Blog Archive » Tilt SCREAM Pong

Tunnel- A game that uses the SMS to control the direction of the spaceship in order to avoid the protruding walls.

Note: No AMS2HID necessary to activate the SMS controlling.

Download from Download Tunnel for Mac - Arcade game for laptops with Sudden Motion Sensor. MacUpdate.com