I still have an IPC on my desk as a monitor stand. In 1996 I used it as a router for my 24hour 56kbps modem connection, serving all of 204.94.173.x - I was paying tlg.org $145/mo for my Class C address space, and all my home machines were just hanging out there. that is the internet I really miss.
I hear you. For most of the 90's, I had my home network on a publicly routed /24, no firewall.
Same! My IPC served my domain using Solaris on a nailed up bonded ISDN circuit until someone filled the root disk trying to patch the rpc.cmsd remote exploit. After that it was BSDs until I settled on OpenBSD.
I have been thinking about getting an old IPC or IPX and swapping out the internals with a modern PC motherboard and components, but only if I can do it cleanly. I haven't done it due to not having enough free time and... it just feels wrong to me in some way.