SMF 2.0+ Modification.  I will not back support this mod to older versions.

This modification adds a unread PM counter to the favicon.  In addition it continues to check for PMs at a specified interval.  Setting this variable to lower can result in server degration/performance issues.  Use with caution.  The default timeout is 1 minute (60 seconds).

Prior to asking for support, check out the wiki: https://github.com/jdarwood007/smfmod-faviconindicator/wiki

Credits for this ability go to Tom Moor for creating Tinycon: https://github.com/tommoor/tinycon

Browsers that support this:
Chrome 15+
Firefox 9+
Opera 11+

The following browsers will fall back to changing the title due to lack of support for this:
Internet Explorer 9
Safari 5

Websites with apple icons meta data may not function as iOS/Safari may overload the favicon