Just a thought - sometimes a site can get blacklisted on a web/internet security/antivirus site.
What OS (Mac or Windows X)
What browser
What Antivirus.
Try turning off your anti-virus packages web protection element for a bit and see if this lets you in.
If someone had tagged us as a bunch of dodgy reprobates due to the images in a certain thread and your settings are on high protection it could be this?