7.  Selection structures, if, multibranch if, dangling else, switch
    statements (NOT supported by TinyVM). break.  ActionListener.

*) Subsumption based program (see lab 5)

*) Extend the Button class to provide a ButtonListener functionality.

*) Timer listener, Sensor Listener.

*) Brightest Light Seeker w/ obstacle avoider. 
   (Baum's book has something like this, for mechanical design)

*) Darkness Seeker -- something which tries to find the least amount 
   of light.
   
*) Table edge avoider (pg 90 constructopedia)

*) "Remote" control (pg 91 constructopedia).
   (Baum's book also has something like this).

*) display input of a specific sensor based on which button is
   pressed.