Mailing List App

I'm looking for an open source Mailing list application that users can go online to a website and subscribe to. It would need multiple lists so users can choose which lists to subscribe to. The other thing is that it needs to be Remotely hosted. We currently have a hosted one and everytime we send out an email it goes through our SMTP server, which crashes the email server for the entire organization when we sent to many many subscribers at once. We are currently in the process of possibly switching email providers, so we do not want to try and remedy the situation internally, and are looking for a remotely hosted option.

Thanks in advance!

Out of curiosity, why does it need to be open source if it's going to be remotely hosted? I doubt you'll be able to find one like that (and even if you do, I doubt it will be free, especially if you have as many subscribers as you seem to indicate and want multiple lists).

EDIT: Depending on what you're looking for, Aardvark Mailing List may fit the bill. It's free, remotely hosted, and supports multiple lists. It isn't open source, though (at least, not as far as I can tell), but if you meant "free" when you said "open source," (as many people often do, including myself) then it's possibly just the thing.

Just keep using the same software you're using now, but put a throttle on it so that it only sends out emails every 8 seconds or so- that should be low enough bandwidth to not crash your server.

and also it may have less chance of being seen as spam ...

If he uses what he has or goes with something like Ardvark? Please expand on your answer. Thanks!

no, when the messages don't go all in one row, like if you let the thread sleep for 20 seconds or so before sending the next message ...