Starting June 29, Virgin Mobile will offer the no-contract Apple iPhone 4S 16GB Prepaid Smartphone for Virgin Mobile for $649. Although we've seen iPhones sold without contracts in the past, this is only the second time any iPhone has been offered as a prepaid phone. (Cricket Communications announced its prepaid iPhone last week.) Sales tax is added where applicable. Virgin Mobile's prepaid plans will start at $35 per month, although registering for automatic payments will earn a discount of $5 per month. The basic plan will include unlimited texting and data and 300 voice minutes, while upgraded plans will feature more minutes.

Of note, Virgin Mobile will also offer a no-contract Apple iPhone 4 8GB Prepaid Smartphone for Virgin Mobile for $549.