I'm pretty new to Linux, so I expect to have to do a lot of reading and experimenting to get this going...

My question is not 'how do I do it?' it's 'Is it possible and realistic for a newcomer?'

I want to set up an IMAP email server so that I can log on to a Linux machine (holding all my emails) from my laptop, a second desktop machine, or maybe even from out on the road. The network is already up and running.

My current email setup is via a fixed IP with my internet service provider, and I download my emails via pop3 and send them using their SMTP service. What I want to do is to get my emails from my ISP via pop3 and then store them on the Linux server, distributing them via IMAP when I log in from another machine. I'll still use the ISP's SMTP service for sending.

I have a Debian 'sarge' distribution and was thinking of using dovecot and exim-4.

I just thought I'd ask first to make sure I'm not attempting the impossible!

Totally possible, and you will learn quite a bit in doing this. Good project.

You might look at the fetchmail utility. It can download the POP mail to your Linux machine, as a daemon or on demand.

From there, it's not that hard to put together an IMAP server that can give you access to the downloaded emails. There are a couple different formats for storing mail in folders on your server. Just make sure you choose an IMAP server that plays well with whatever client program you'll be running when directly logged into the Linux machine.

Use encryption wherever possible.

Mutt is a nice console mail reader. Learning curve, but worth it due to the flexibility.