If you're sending e-mail via SMTP (I assume so since you're talking about Eudora) then you can do it with any database software that can export a text file. There are tools out there for sending mail from the command line, similar to the sendmail utility on Unix (I think there's even a sendmail for Windows). All you would need to do is use your database program to generate a command line script that you could then save to a text file and execute from the OS.