Adding the following to /etc/hosts (or windows\system32\drivers\etc\hosts or somesuch on windoze) gets access to the site and OpenID works fine for me
75.101.180.111 britcoin.co.uk www.britcoin.co.uk
Everything works as expected once logged in with a fudged entry in my Hosts file - so all transactions etc are not lost.
This looks to me like the domain has been hijacked?
Andy