Howard is a mail client that notifies you about incoming messages on your personal account. You will receive subtle visual and audio notification whenever someone sends you a message, and you will have the chance to check it on the spot.
The program installs as a small icon placed on the system's upper bar, changing its color from blue to red at each incoming e-mail. At this moment, the Mac edition of the tool supports only Outlook.com and Gmail.com. Other web-mail services stated on the developers' official site seem to be available strictly for the Windows version. Therefore, Mac users who have accounts with other mail providers other than the two I already mentioned will not be able to benefit from Howard's services.
Supposing you are an Outlook or a Gmail registered user, you need to log in to the corresponding account in order to be notified of incoming messages. As I anticipated in the introductory paragraph, both visual and audio alerts will inform you whenever a new e-mail is received. What is great about this tool is that you have the ability to select a favorite sound alert – namely, you may select one of the sound profiles provided by the program or you are free to choose your favorite track. Furthermore, you have the ability to determine a regular time interval for checking the receipt of new e-mails, or you may perform a manual check any moment you want. To view the messages you've just received, you need to install another mail client or you may just use the Mac's Mail App, which works just fine. more
Google Notifier keeps you up to date with notifications of new mail and events.
Command-line tool to send Mac OS X User Notifications.
Messaging application designed for Mac.
Ever wondered what the song you just started to play in iTunes or Spotify was?
Add-in to iCal that gives the user options for how replies to meeting invites that are sent with Mail are dealt with.