Herald Plugin For Mac
If you are looking for free plugins for your email client on your Mac then you should take a look at this site here. They have a free plugin for use with Mail app, which is the email client for MAC OS X users. This plugin notifies you with a popup when you receive new email and allows you to perform several actions from the popup, see the website for more info and to download the free email plugin.

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Wordpress Plugin If you use Wordpress then you must download this free plugin for use with it. You will be able to build your own lists and be able to mass mail it.
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Fun Letters
No Spyware - and No Adware - And, unlike similar stationery, you don't need to download a separate, bloated email program to use Funletters. and they do not track your email. providing you with a fun email experience without worrying about spyware, adware, or junkware.Funletters for Outlook Express are easy to use, quick to send, and FREE! Many of the Funletters are animated, and are available in a wide variety of popular choices.

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Sendblaster Get yourself a free copy of the SendBlaster software which is a feature packed email client and is compatible with all the Windows operating systems including Windows 7. It is completely free of all spyware, adware and viruses as certified by softpedia.
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Anti Spam Classifier You can download this free anti-spam plugin for use with most versions of Outlook, Thunderbird, gmail, hotmail, and more. Take a look at the site and see if it supports your mail client and operating system so you can use this plugin which will not cost you anything.
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Email Tag Plugin At i-fax.com you can download their email plugin for free. The Universal Document Tag will work on Windows XPNT2000 servers and also Unix and Linux servers.
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Drowning In Email? Xobni is the Outlook plug-in that helps you organize your flooded inbox.
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