One which needs to be opened to users/owners instead of locked away. A price-doubling 100% sales tax on Universal Machines which lock owners out like with video cards (and their firmware), should make products which are not fundamentally significantly GNU-ideals friendy unaffordable to the average consumer (and therefore not economically viable anymore). Siemens can still sell their $5MM machine for $10MM to BASF or whatever, because BASF can afford to borrow double to pay the tax, but Cletus and Dorothy will not be buying sony playstations and apple iphones because $2,000+ isn't worth it.