Once you install xterm, there is access to the command line:

http://maemo.org/downloads/product/osso-xterm-advanced

The "entire" unix command catalog on a device with a 256mb flash root is sort of a tall order though. That said, I'm a new owner and I've been able hunt down everything that's important to me pretty easily. Including:

ssh client/server, openvpn, samba/cifs client, rsync, subversion, e2fsprogs, cron, gnu tar, wget, etc.

It doesn't come with all of the common nix utilities by default. For example wireless-tools for iwconfig needs to be installed separately, it uses a different shell than bash (again, you can install it if you wish), and some programs like man and stat seem to be unavailable.

Circuit City carries the N800, but their online database doesn't admit to having it in stock in Minnesota.

The shell and many common Unix utilities installed by default are part of Busybox, which is a single binary that combines a lot of functionality in a very small package. It's fairly common on embedded Linux systems, such as routers and print servers, because it saves bytes. Some of the utilities have only the basics implemented, but they're the basics you'd most commonly use.

If you install sshd, you can connect from your desktop machine and poke around. By default, ssh sessions as "root" are allowed. The default root password is "rootme," and you should change that right away if you install sshd.

Yeah, they didn't even know what it was. I tried. Rrrrr.

It's pretty certain I'll get one anyway eventually. But it'll probably take a bit longer than if I could see one at a store (that said, I'd probably look at one at a store and then get it for $70 less online, which I'll end up doing anyway).

I would do a search on Nokia kiosks in your area. Not only can you play with the N800, but other Nokia N series are also available. I was lucky to have a kiosk in my area before I shelled out the bucks to buy one. The kiosks are commonly found in large shopping centers. Good luck.

Urrrr... where do I search for those? All I see on nokia's website are "flagship stores".

Dude, if you're lookin' for a portable device that you'll end up keeping in your pocket while you ssh in from your desktop, welcome home! You know the rest is gravy!

Oh yeah, it'd be more available to demo if they were aiming mass market yet. Right now, you have to need it. You feel the call...