Hosted SMTP Server Recommendation?

Can anyone with a deployed Rails app recommend a reliable hosted SMTP
server that they use? I know that Gmail will let me send up to 500
emails/day, but I have an app that will need to send thousands of
(legitimate, non-spam) email per day.

I've heard that it isn't terribly difficult to set up my own mail
server, but we're a small company, and as such, we need as small of a
stack to maintain as possible.

I've looked around Google, but it seems very difficult to find a host
that provides a pre-configured SMTP server with flexible daily sending
limits. Probably because many of the people that would want something
like this are spammers.

Bill Harding

Most of the Linux VPS systems I’ve worked with have sendmail installed, so you can use that with Rails instead of SMTP to send messages. I have no idea if that would handle your volume or not, but it certainly works great for us.

Try installing ZIMBRA on one of your servers.