When I read that Apple’s iPhone 3G was going to be made available on a contract-free O2 Pay & Go tariff in the UK, I thought that perhaps I would finally climb aboard the iPhone train and discover whatever I had been missing. But after a little ‘research’ and number crunching, it appears that as an option to the original iPhone on an O2 contract, things don’t seem to be that much cheaper. I won’t go again into the…