How does one install linux on a 1gig drive with 16meg of memory. I always here people build boxes with such low specs for routers, firewalls, and VPN boxes. Can any flavor of linux be installed on a low spec machine or is there a certain distro? I am just curious.

Just about any distro can fit on 1GB but you would probably be better going for one of the smaller distros to make sure you don't get bogged down with things you don't need.

I think Slackware would be a good choice if you only select the base/network/whatever else you need packages. If you choose to go with another distro the biggest factor is going to be whether or not the installer can run with only 16 megs of RAM.

I've got slack 9.1 installed on a p90 with 16MB ram and a 300MB hdd. I guess that answers the question

what packages do you have installed on your Pentium 90 and what role does it play?

I have (roughly) everything except X11, Gnome, and KDE (and related packages) installed on a Pentium 1-MMX with 16 mb of ram and a 2 GB HDD. With a 300 mb swap, 53% of the hdd is used post-install.
Then again, I don't have a monitor attached to it (it's only in use through SSH), and you may want something extra extra lean - like fluxbox.
Regardless, it's fit for a web server, an ftp server, or basically anything you want... it's just going to swap a lot, with 16 megs of ram, and be extra slow.

Edit: Sorry, I've just noted that you only have 1 gb - just tailor it for what you want.

You'll want to have a very specific use for this box if you were to install any distro on this box.
16MB of RAM is only well suited for a dedicated firewall and/or NAT box.
You would probably want to be very selective with what you install (i.e. no graphics, games, X, sound, and anything else not related to the specific task at hand. I have a few linux boxes with 32MB of RAM and 1GB of space that serve as great firewalls.

BTG

If you want a firewall/router go with coyote linux. If you want a distro based on old version of things (files that were new when that computer was new) then go with deli linux or an old version of slackware. New versions of FreeBSD and Slackware will both work. If you want something quick you could also try DeliLinux or Damnsmall linux, they have very few options to configure, but get the job done. (Damnsmalllinux IS a live CD, but HD installs are possible)

Just basic network stuff really. I was going to use it to replace my smoothwall box with a quieter machine but the pcmcia nic had a bit of a dodgy connection so I put it to one side and never did any more with it. I'll get round to it eventually.

I would sugest Damn Small linux. It's a 50MB iso, it comes with just about everything you need, editors, X windows, Fluxbox, internet, email... I use it on one of my computers.