One Unique Case Where IPX/SPX May Help

If you have more than one computer, and you connect your computers directly to the internet, with public ip addresses for each computer from your ISP, you absolutely must have a personal firewall installed, and properly configured, on each computer.

You'll need TCP/IP on each computer, for internet access. But without a router to protect your LAN, please don't setup file sharing between the computers, using TCP/IP. With file sharing over TCP/IP, you'll have to open holes in your firewalls. And if your computers are not protected from the internet with a router, whatever your computers can see between each other can also be seen from any computer on the Internet.

Depending upon your Internet service, there's no guarantee that the addresses you get will all be on the same subnet. And different subnets means no browsing capabilities between them, even if you do setup file sharing.

This is (one of the very few cases) where you need to use IPX/SPX, or possibly NetBEUI, on your computers. Neither IPX nor NetBEUI pass thru routers, so it is only visible between directly connected computers. Install and enable IPX/SPX or NetBEUI, and unbind file sharing from TCP/IP, on each computer. Be sure to setup all computers the same way; leave file sharing bound to IP on one computer, and you may be seriously exposed.

Steve Winograd explains how to setup your computers using IPX/SPX (or NetBEUI) for file sharing.

A far better solution would be to get a NAT router, and share one public IP address. By not paying for multiple IP addresses, you could save enough money to pay for the router in a few months, and after that, who knows what you could find to spend your saved money?