This is a simple project using the LaunchPad from Texas Instruments and Energia (Arduino-like IDE).

The Launchpad version 1.5 comes with the MSP430G2553 microcontroller, it has a hardware UART (use the  jumpers as shown in the image).

This is a funny and very low cost project.
The LaunchPad measures time (in microseconds) .The car travels a fixed distance between contacts (10 Cms).

Time is measured using  START and STOP contact switches.
Contact switches are implemented using neodymium magnets.

You’ll need small nails, miniature neodymium magnets and colors headed pins to  assemble the switches.

Here is the code used:

/* Cronometer01.ino
  Arduining.com 25/AUG/12
  Used in the LaunchPad V-1.5 with the MSP430G2553
  Measuring time between the signals of START and STOP  in microseconds.
  The result is sent serial at 9600 bauds.
  
  GREEN LED on indicate READY TO START.
  RED LED on indicate MEASURING TIME.
  RED LED blinking indicate MEASURE DONE.
  
  Push RESET in the LaunchPad to repeat the measurement. 
 */
#define START  11     //Pin P2.3
#define STOP   12     //Pin P2.4

unsigned long time;

void setup() {
  pinMode(START,INPUT_PULLUP);  //internal pull-up
  pinMode(STOP,INPUT_PULLUP);   //internal pull-up
  pinMode(GREEN_LED, OUTPUT);     
  pinMode(RED_LED, OUTPUT);
  Serial.begin(9600);  
}

void loop() {
  Serial.println("READY");
  digitalWrite(GREEN_LED, HIGH);   // set the GREEN LED on
  digitalWrite(RED_LED, LOW);      // set the RED LED off

  while(!digitalRead(START)){}
  time = micros();
  digitalWrite(GREEN_LED, LOW);    // set the GREEN LED off
  digitalWrite(RED_LED, HIGH);     // set the RED LED on

  while(!digitalRead(STOP)){}  
  time = micros()-time;
  digitalWrite(RED_LED, LOW);      // set the RED LED off
  Serial.print(time);
  Serial.println(" Microseconds");

  while(1){                        // Blink to indicate END.
    delay(900);                    // wait 0.9 second
    digitalWrite(RED_LED, HIGH);   // set the RED LED on
    delay(100);                    // wait 0.1 second
    digitalWrite(RED_LED, LOW);    // set the RED LED off
  }

}

See it in YouTube:

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