When a website that is running locally tries to access a remote web service.
XMLHttpRequest cannot load Origin http://127.0.0.1 is not allowed by Access-Control-Allow-Origin.
To disable this security restriction in Mac Chrome
open -b com.google.chrome --args --disable-web-security
See also:
http://www.nczonline.net/blog/2010/05/25/cross-domain-ajax-with-cross-origin-resource-sharing/