[ALUG] SBCs that run Linux - someone mentioned some a while ago

A while a go when we were discussing low-powered backup solutions someone here mentioned a couple of Linux based SBCs (Single Board Computers). At the time I was looking for something somewhat different but now I think I might have a use for such a device. Can someone point me in the right direction (the mail list archive isn't searchable so doesn't help much as I haven't a clue how long ago it was). -- Chris Green