Okay, so my school computer is behind a firewall. I can't remote login via shh because my entire building is NAT'ed to the same IP address (and yes, it crawls). My dorm room does have a good-ol-fashioned analog phone line though, which I never use.

So, I'm wondering if I can dig up a 56k modem and dial in to my computer. I know this used to be relatively common. Is telnet the tool for this? I've been looking but the telnet tutorials reference an awful lot of IP addresses and not many phone numbers, so I think I might have that wrong.

So what is the proper daemon to run to allow dial-in access to a computer?

Are you trying to access from outside the schools network? If so of course they are going to have a firewall! Otherwise It wouldnt be a very good school.

You should be allowed access with VPN. They have to provide a way for people outside the network to get in. Ive never heard of any other way then VPN. Anyways check your schools help desk website, details should be listed there.

Really try to avoid going through this method, unless you want to do it. Here is a full how-to:
http://www.howtoforge.com/linux_dialin_server

Good luck.

I asked, and the vpn is only available to faculty and staff. The college contracted their network out and didn't pay for student vpn I think. Ideally, I'd like to just phone in, then find some way to connect from there back to the remote machine via some more standard procedure.

Are you going to put a modem and phone line at both ends? That is about the only way you are going to get around the firewall issue.

Indeed, that's the idea, a modem at both ends.