I've been running FreeBSD and Linux for several years now. My original box was a 486 running FreeBSD 2.2.5. Now I have a motley collection of 486s and Pentiums running recent 4.x releases. Before we went to a broadband connection at home my dialup server had nearly a year of uninterrupted uptime.
On the Linux side, I've tried several distributions. My favorite is still Debian, but I've also tried Red Hat, Slackware, and Mandrake.
I used FreeBSD for several years on a network project at a local public library. The library has since gone to broadband, but FreeBSD powered a dialup server on a 486-33 and served up patron Internet access for thousands of dollars less than the commercial solutions that were considered!
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