I currently have an OpenBSD firewall running on an ancient 286. I have a mini-itx board, CF/IDE converter and a CF card and have been intending to upgrade to Debian
See it here
However – rather than OpenBSD I'm going to try for debian (since I know that much better).
This post will end up being a “how I did it” – but at the minute is just a collection of the notes I'm grabbing for now.
I am going to start by hanging a CD-ROM on the IDE channel and using the netinst CD.