Opera 10 has a nice turbo mode where all requests are re-routed to Opera's servers (
global-turbo-x.opera-mini.net ) where the pages are compressed and sent back to the client browser. Consequently all requests to a site arise from that server instead of the actual server.
Yesterday I was unable to access SO[FU] from Opera. Initially I thought SO[FU] was down, but when I checked from my iPhone, the sites were accessible. I tried again in Opera, this time with "Turbo" mode Off, and yep I was able to access. Turn it on, and SO[FU] just refuses connections.