A number of MMOs have become inaccessible from inside Iran, apparently due to government bans on specific content.
Players on the Battle.net forums have reported finding themselves locked out of Diablo 3 and World of Warcraft.
One affected user claims the missing games are probably the result of a conference held by the Ministry of Culture and Islamic Guidance earlier this month, which ended with the formation of a group called the Islamic Revolution Game Designers Community, tasked with banning games that include or promote superstition, mythology, violence and revealing clothing.
According to responding players, it's not just Blizzard games which have been affected so far; Guild Wars, RuneScape, Second Life, Dofus, Evony and Entropia Universe were all mentioned.
Most major publishers do not distribute games in Iran, and piracy is rife as a result; you may recall a somewhat amusing Battlefield 3 ban which saw the Iranian Government cracking down on pirates on EA's behalf.