Is it just Wikipedia that won't load? Try typing 145.97.39.155 into
the address bar - that's the IP address for
en.wikipedia.org. After a
quick test, I see it won't actually take you to the main page, it will
take you to an error page (with the foundation logo) because it
doesn't know which project you want - let us know if you can see that
error page. If you can, it sounds like some kind of DNS issue. If you
can't load that error page, and it's only wikipedia that's a problem,
then something very odd seems to be going on...