Email notifier that runs in the Windows task bar and alerts you when you have new email on any of account.

Official site : For more information
Features:
Easy Setup - accounts are imported from your existing email client(s)
Supports POP3, IMAP (including GMail, AOL, AIM, Netscape, FastMail, etc), SMTP, GMail, HotmailMSNLiveMail, Yahoo, Mail.com, MyWay, Excite, Lycos.com, RediffMail, Juno, NetZero
IDLE is supported for IMAP accounts which allows instant notification when new mail arrives in your inbox
Read, delete, print and reply to Email without opening your email client
HTML email support
Password protection
Address book
Options to protect you from messages that contain viruses and web bugs
Send, save and open file attachments
Run POP Peeper off your portable storage device
No account limit -- notifies you of an unlimited number of accounts
Many ways to receive new mail notification: skinnable desktop alerts, audio, flashing scroll lock LED and more
Specify how often all accounts are checked for new mail or set individual intervals for each account
Extensive help with useful tips and information
Email Notification Options
Sound notifications: single sound for any new mail, or a customized sound for each account
Tray icon notification that display the color and number of new messages for each account
Flashing scroll lock LED
Windows popup alert indicating which account(s) received new email
Automatically open POP Peeper or launch your email client when new email is received
Skinnable popup (optional download)
ScreenSaver (optional download)
Chime can repeat a sound until acknowledged andor launch another program when new mail arrives (optional download)
What's New:
New connection option, "Assume always online" for certain internet connection types
New option to adjust font size for HTML-based messages
Fix: Imap: Idle wouldn't engage if polling interval was even number
Fix: Imap: Potential crash when using SSL and server disconnects unexpectedly
Improved Date/Time formatting parsing for certain languages
Fix for archiving webmail-based messages
Fix for reply-to when including a name
Fixes for some cases where HTML view wasn't using the correct character set
Fix for checkmail trayicon showing even if relevant setting was disabled
Fix: when viewing HTML, links with anchors would not open to the anchor and just open at the top of the webpage
Fix: Size column is right-justified
Fix: When viewing a message in HTML and clicking on a link, the anchor wasn't being sent to the browser (when applicable)
Fix: In certain cases, an empty account name was allowed to be created
Checking accounts using a folder will result in error if Add-on Pack isn't activated
License filepath can be specified via ini parameter
Imap: Misc fixes
Imap: "Deleted" is detected as an alternate name for "Trash" folder
Smtp: consecutive errors will suspend further attempts to send the message