Majordomo is one of the most popular. but it runs on linux only.
some people scritp this sort of thing with Blat.exe (do search on google) for the latest version.

what os, are you looking to run this sort of thing on. ?
do you already have a smtp email server. ?

Here is another solution.
Bob Lee


>Hi people,
>
>I've got a database with 80,000 email addresses and our marketing department wants to use them for diverse campaigns (announcements, bargains, special offers etc.). I know there are emailers available out there for download but which one would you recommend us?
>
>Thanks for your comments,