[TriLUG] Mass mailing ideas

[Douglas Ward]

We are in the process of migrating 1300+ e-mail accounts from one system to
another.  As part of this process I must take a spreadsheet with 1300+
e-mail addresses and new passwords, insert the information into a form
message and send it out to every account.  Has anyone done this before?  If
so, what tool(s) did you use?  I prefer a tool that I can run on my Ubuntu
workstation but will consider practically anything.  Since this need will
expire once the migration is complete I'm not really looking for any
commercial software (although I will pay for brief usage if the service is
compelling).  Any advice would be most helpful and appreciated.