wow. Interesting, impassioned and highly personal response to a simple stimuli. Seems like over reaction. Double blind testing in a controlled setting is a reasonable way to discern whether actual differences can be heard. And... as Schipo points out... well the data is in and here is what it says... even professional audio reviewers could not distinguish between power cords.
That is not to say that people cannot enjoy one cord over another in their system --- people who enjoy tweeks and derive pleasure from modifying and experimenting with their system may like one PC better than another in their system. And, if so, good for them and it is money well spent. That does not, however, change the fact that trained audio professionals whose living it is to review audio systems could not distinguish between PCs based upon sound alone.