A couple of Aptrix sites I've been working on are:
http://www.actelion.com/
http://www.weforum.org/
my own sites -- http://www.rtlib.com and http://www.ls2capi.com are
done in plain Domino, are rather neat and contain about thousand of
documents each. Not that i ever have too many guests, but if they
sometimes get slow then only because of other applications on the
shared host;-)
Frankly there are not so many websites that could be done in a more
efficient way by NOT using Domino (discounting the eventual licensing
costs as maintenance will probably be the same or better). Some really
cheap private stuff on free diskspace of internet provider or the
really big stuff grinding thousands of transactions per minute against
the backend enterprise systems. And of course small to medium sites
with little demanding requirements, with limited or no security could
be better done in whatever media you feel more at ease.
Just one advice -- whatever you do, do not rely on Domino rendering of
rich text as HTML. If you care how it looks that is. It may slow you
down a bit, but the default rendering is slightly-to-medium
nauseating.
Regards
Normunds