There was a crackdown on internet usage in Iran last year but not for the reasons you might think…
"While there is concern that porn, and things offensive to Islam, are freely available, no one has yet decided to filter it. Opposition political parties are also given free reign."
So what caused the crackdown? Voice Chat.
"So many people were using it, instead of their more expensive telephones, that the loss of revenue at the nationally-owned phone company was too great for the government to bear."
Sounds positively western.