The Linux Foundation asked its people to wet their pencils and figure out the total value of Linux and the effect the open source platform was having on software economics.

And so according to their calculations it would take $10.8 billion to build a Linux distribution like Fedora 9 these days from scratch and $1.4 billion just to develop the Linux kernel, but the ciphers are so weighed down with qualifiers they don't seem worth the bother.The point of the exercise, aside from the obvious propaganda value, was to update David Wheeler's 2002 study which claimed - based merely on its lines of code - that a typical Linux distribution was worth $1.2 billion.

He used Red Hat Linux 7.1 as his touchstone. The new reckonings use Fedora 9, which includes 204.5 million lines of code in 5,547 applications packages and probably took 60,000 man-years to write.

Linux Foundation uses a 2008 salary calculation to come to $10.8 billion but immediately cautions that this is a US number from the US Bureau of Labor Statistics and of course Fedora isn't purely a US product any more than the Linux kernel is - and the kernel's seen contributions from 3,200 developers from 200 companies in the last two years.

The number doesn't transfer that well since distributions like Debian are bigger - even different versions of the same distribution represent significant differences in lines of code - and the Foundation can't quite come to grips with issues like testing, which it figures is an order of magnitude higher than for, say, Windows if for no other reasons than the distributed nature of open source developers and standalone projects.

It also concedes that the amount of effort that goes into deleting and changing code, not just adding to it, is not reflected in its estimates. But it figures that "because in a collaborative development model, code is developed and then changed and deleted, the true value is far greater than the existing code base."

It's also not sure how to factor in the effort of writing code that doesn't make the final cut.

According to an IDC study run up earlier this year, Linux represents a $25 billion ecosystem and according to the Linux Foundation Google "borrowed $1.3 billion worth of R&D from Linux to introduce Android." Ditto Amazon Kindle and Linux-based netbooks.