PicoBSD
PicoBSD was a single-floppy disk version of FreeBSD, one of the BSD operating system descendants. In its different variations, PicoBSD allows one to have secure dialup access, a small diskless router, or even a dial-in server, all on only one standard 1.44MB floppy. It runs on a minimum 386SX CPU with 8MB of RAM (no hard disk required).
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