If you can hear faint giggles over at Apple's HQ in Cupertino, it could be because executives there are rolling around in mountains of cash. They've even been seen throwing it in the air and lighting cigars with it. Why?

Because Apple's benefiting from an advantageous iPhone deal that sees AT&T hand over $18 (£9) per phone per month for the life of the two-year contract, according to Piper Jaffray analyst Gene Munster.

Here comes the maths bit

Team that with recent iSuppli figures which show that the iPhone costs $399 to buy, but only $265 to make, and you'll see that Apple makes a clear profit of $565 (£276) per phone over two years.

Multiply that with the fact that Apple is roughly selling to 1.8 million iPhones per quarter and those hard-pressed Apple bigwigs could well be using greenbacks as loft insulation, earning $1 billion profit per quarter spread over two years.

Now not even the Mafia can get score deals this good. But then there's a great deal more to this numbers racket than that.

The numbers racket

First: Gene Munster simply may have his numbers wrong. Citibank's Richard Gardner says that Apple gets nearer $12 (£6) per phone per month. That's only $425 (£207) gross profit over two years once you factor in profit made on the iPhone hardware.

Second: Knock off the $86 million (£43 million) Apple has lost by buyers not activating their iPhones on AT&T, plus the $40-$50 per customer AT&T usually makes, and some are even suggesting that the iPhone is actually costing both companies money.

The only thing anyone really knows is that Apple's having one helluva year - and we still have two months to go.