Do you need to be able to make money only legally?

This was a very interesting comment from von Lohmann (again from the 9th circuit):

von Lohmann: Yes. And in particular there I would direct the court's attention to the Fifth Circuit's ruling in the Vault vs. Quaid case, where it was conceded that the noninfringing uses standing alone would not have supported a market for the product at all. Nevertheless the Fifth Circuit found that the product in question was capable of substantial noninfringing uses. In other words, the court refused to imagine a hypothetical product where the infringing and the noninfringing uses had somehow been segregated and then imagine a market and attempt to figure out whether one or the other would sell.

It's a very interesting point, if today somebody calculated that 90% of CD burners sold were used for illegal purposes, could we ban the CD burners because if those sale were removed, we would have a non-viable commercial product?

Still I think the issue will gravitate around the fact that Grokster has "evil" intentions and could potentially do something about the abuse that is used with the help of their software.