Duplicate Email Remover 

Delete duplicate emails and posts in Outlook and Microsoft Exchange Server folders; search across your folders. A duplicate found can also be marked, copied or moved to any other folder. Works as an add-in for Microsoft Outlook 2000-2003. Free trial.
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Essen Filtor 

Simplest way to filter business emails from a text file, containing list of email addresses. You can use any text file and feed them to Essen Filtor, it will quickly grab all the email addresses from the file.
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