AboutUs.org
<http://www.aboutus.org/Wikipedia.org> also makes interesting
use of an infobox in every article. Their stuff is almost exclusively about
web domains, so obviously it's external links and the like. But the
interesting part is that they can point to a section to glean address info
from (they don't do it on the wikipedia domainpage), thus being able to use
a Google maps function. This might be really cool for appropriate geography
articles on Wikipedia.