You can buy used epia boards - fanless EPIA EDEN 5000 is enough for linux. It is really cheap. I couldn't find EPIA EDEN 5000 so I bought EPIA 800 @133Mhz and UNDERCLOCKED it = 400 @66 Mhz. It is running fanless now. Even underclocked - it is faster and more responsive than pIII733 winXP fileserver.
Special Linux distros... hmm... I would have thought any normal distro would run okay, given that the board is X86 compatible?
Yes. Any x86 distro wold be ok. No prob. here
"Special" distro = compiled exactly for given epia type motherboard = slightly faster or smaller, especially for router/server etc.
"special" distros are a bonus, not a downside.
You can try clarkconnect.com. Excellent distro with web based management.
I don't know your linux skills, but i've started my linux adventure with clarkconnect. Few mouse clicks... and you have fully featured web/print/file server. And the HOME edition is free. Compared to pro - it has no support or help desk. No big deal.
And the web configuration panel is EXCELLENT. Of course you can still use ssh/putty.
But hey... Is that cobalt cube ok? Is it working? You should try install linux on that box without ripping off the old hardware.
Check out linux MIPS wiki: