For those who don’t know what exactly favicon are, it is a tiny image used for easily recognizing a website, which can be seen behind the address bar. As you can see in the image here, the ‘Gmail Logo’ is the favicon for Gmail along with which the total unread mails count can be spotted.
So, if you are a Gmail addict like me, all I would say is just go and install this script. Also, before installing the script be sure that you are a firefox user with Greasemonkey installed in it. Oops!! I forgot to mention, as greasemonkey is only for firefox, the script can only be used in firefox. 😉
Links: Greasemonkey | Gmail Unread Message Count Script
Script Credit: Lifehacker