For those of you who are Gmail users and would like to have a solution of mail notifier then try:

CheckGMail

CheckGmail is an alternative Gmail Notifier for Linux and other *nix systems. It is fast, secure and uses minimal bandwidth via the use of Atom feeds.

CheckGmail is a system tray application that checks a Gmail account for new mail. When new mail is present the tray icon changes, an optional animated popup is displayed and a tooltip displays the number and details of new messages. Configuration is GUI-based and the application is designed to be simple, elegant and unobtrusive.