One cannot help but be amused by the great Worstall – slayer of the Greens – carrying multiple adverts for WWF on his blog (above – slightly tidied up: click the link to see the real thing).
I am sure there is a good free market rationale for carrying the propaganda of one's enemies for commercial gain, although I have to admit that it is a little bit difficult to work out. Personally, I prefer the donation model (thank you everybody) rather than turn this blog over to content I cannot control. But then, that's the "free" market for you – take the money and surrender control.
Thus says Tim Worstall (by default): buy a cuddly toy from WWF and save the planet. You know it makes sense.