>> www.netbsd.org should be available 24/7/52/385/whatsoever...
>
> Of course it _should_.  I'm not saying anything different.  But if it
> _does_ go down and one needs a mirror, trying www.<cc>.netbsd.org is a
> safe bet.  That's all.
>
> -Jan

i was working for an ISP a few years ago, we had a similar problem (we 
wanted www.blah.org available uninterrupted but had no money to build 
up another BGP peering etc etc) which we solved using two 
(equal/similar -- there were two Macintosh Server G3) machines and DNS.

it run perfectly :)