Officially our best-ever cease and desist
The sad thing is, the NPB may have had a valid point here. Unlike most forms of intellectual property, trademark rights do degrade if you don't defend the mark and it is deemed to be diluted. I'm not sure the ThinkGeek guys got this, since they referred to parody as a defence, and that would normally be used in connection with copyright. So we can all have a good laugh, but there might be a real point about the appropriateness of various legal standards for defending intellectual property rights as well.