Okay before you all patronize me about still being on dial up keep in mind that I am right along the border in manitoba so there is verry little chance of high speed.
I run dial up and have 2 PC's and a Mac, what I am doing right now Is I have all my computers plugged into a 24 D-Link switch that then plugs into the router, I have one laptop that is dedicated to serving up a dial up connection to the rest of the computers on the network including anything connected via wireless.
What I would like is a linux/Unix based way of doing this sharing so that the laptop I have serving the connection doesn't get viruses and serve them to the other PC's on the network.
Lots of folks still use dial-up and even have both hi-speed and dial-up accounts.
This can be done using a basic linux distro if you want to continue to use the laptop as a gateway. But there might be an easier and cheaper way that might free up your laptop. If you can find a Multitech home router or a USRobotics 8000 series home router; they had a serial port backup for the WAN port that permitteed them to use an external modem for dial-up. The USR should be available on e-Bay fairly cheaply. The Multitech I think may still be in production. I do know some Netgear and Zyxel routers still have serial port fallback but that's a more expensive solution.
Obsolescence is just a lack of imagination.