Sometimes its just too inconvenient to log in to your web-based email account to check whether there is any new mail. It is worse if you have multiple accounts. Generally, you can seek help from a notifier program. A notifier program can tell you at a glance if you have got new email by alerting you from your menu bar or taskbar.
There are many forms of Notifiers, from shareware to desktop widgets for Windows and Mac OS X systems. If you are using Gmail or have a Yahoo! email account, you can download a Notifier to keep track of new messages.
Click this link to download the free Yahoo! mail Checker
Click this link to download the free Gmail Notifier from Google.