Fvicon.com offers an API that allows users to retrieve favicons from website URLs.
Some API methods include retrieving favicons from specified websites, editing the
format of the favicons, filtering the type of favicon returned, and retrieving image
sources. This works better than Google Shared Stuff (S2) and other online favicon retrieval
services.
http://fvicon.com/{url}?type={type}&format={format}
&defaultIcon={defaultIcon}&layout={layout}&includesocial={includesocial}
&filter={filter}&width={width}&height={height}
{url} - required
{layout} and {format}.
{type} - optionaltype=all). If you specify this
attribute, all of the favicon(s) (which includes desktop, iOS version) will be combined
based on {layout} and {format}.
{format} - optional{defaultIcon} - optional{layout} - optional{includesocial} - optional{filter} - optional{width} - optional{height} - optional
To improve performance, can you also specify the sub-domain from a to z or 1 to 9 (NOTE: It should be one character). This will avoid browser connection limits and improve icon loading performance.(Refer Section 8.1.4 of the HTTP/1.1 RFC)
http://g.fvicon.com/http://google.com