[alasdair_]

>The real issue is a patent system that allows someone to refuse to license a patent.

One solution (suggested in the book "Radical Markets" - http://radicalmarkets.com/ ) is pretty straightforward: charge a yearly tax of around 7% on the patent equal to whatever the patent owner claims it is worth, with the caveat that they MUST sell the entire patent to whoever is willing to pay the claimed "value" of said patent - this prevents under-pricing AND over-pricing and ensures maximal societal benefit of said government-granted monopoly.

The book goes into a lot more detail, and the authors have good solutions for the more obvious arguments against such a scheme.