A basic example for using Processing JS in the browser. Example changes the color of the background every second. Based off the "Accessing Processing From JS" example on the Processing JS site

http://processingjs.org/articles/jsQuickStart.html#accessingprocessingfromjs

To run this example, I started a server via the python simple server terminal command

$ cd /dir-of-your-files
$ python -m SimpleHTTPServer

(see http://www.linuxjournal.com/content/tech-tip-really-simple-http-server-python)