The 'Door Switch' or 'Is the Hackerspace Open?' switch has two main software 
components:
1. The microcontroller client code.
2. The webserver database and webpages.

######### 1. The Microcontroller ########
~~ The electrical components ~~
1. A standard lightswitch
2. Diavolino, an Arduino clone  
    -( http://www.evilmadscientist.com/article.php/diavolino )
3. An Arduino Ethernet Shield 
    -( http://www.arduino.cc/en/Main/ArduinoEthernetShield )
    - *note* The linked version is lightly newer, current version does not have
             the Micro-SD card adaptor.
             
~~ The Code ~~
The code is based off of the Arduino Ethernet Shield example code for a web
client.  The micro remembers the last state of the switch, when the state changes
it sends out an HTTP 'GET' request to the webserver to 
'isOpen/logger.php?switch=[0|1]'. A switch state of '0' means the hackerspace is 
closed, a switch state of '1' means the hackerspace is open.

~~ Known Issues ~~
----- Issue 1 ------
After power cycling the switch (aka, the arduino w/ Ethernet shield) the
ethernet shield will fail to connect to the network.  This is apparently a
known issue with the ethernet shield and is related to it not getting enough
juice on startup.  A couple suggested fixes are as follows:
1. Add a 200 ms sleep into the "setup()" function to reduice initial power 
   requirements of the 3.3v line.  I am not sure how well this would work.
2. Add a resistor & capacitor to the "reset" pin of the ethernet shield, this
   also seems to work by disabling the shield until enough power is available
   to charge the capacitor and it then provides a bit more stability on the
   3.3v line.
*. http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1225354009/15
- TODO: Make a GitHub issue related to this issue

----- Issue 2 ------
We should add a feature to somehow alert a user if the "http get" connection
fails repeatedly.  Maybe we should also attempt to ping an address that
absolutely should exist, aka 192.168.1.1 or 8.8.8.8.  If we can contact
192.x then the internal network is good, if we can hit 8.8.8.8 then the
internet connection is good.

######### 2. The Webserver ########
The webserver contains several parts:
1. A MySQL database with a 'doorEvents' table.
2. The logger.php page which accepts 'get' requests from client.
3. The checkStatus.php which polls the database for the current door status.
4. An index.html which uses javascript to refresh the icon when the status 
   changes.