In my teens I ran a combination ipmasq(NAT, this was back when we called it ip masquerading) firewall and dial-up POP for my girlfriend at the time off a scrap 386 motherboard some ISA NICs and a 3.5" 1.44MB floppy drive. It was packed full of SIMMs, I don't remember how much probably 8MB RAM.

The userspace was all in the initramfs, linux booted directly without any LILO or GRUB (this was back in the days the kernel included its own boot loader), and the floppy drive was totally out of the picture once the system was up and running from RAM.

Prior to adding the dial-up aspect for my gf to share my internet from her home, the init was deliberately exited which technically panicked the kernel. Basically it was a /linuxrc shell script setting up the networking then deliberately breaking userspace - not even PID1 existed while it was just my firewall. The kernel keeps doing networking stuff even if panicked.

Fun times.