Power cable hierarchy for components

I realize that there are no definite answers here BUT I'm curious as to what you're thoughts are on inserting high end power cables on various A/V components. Which components do you feel would yield the greatest sonic benefits by adding a high end PC and in what component order would you add them? Various threads on A'gon seem to suggest that digital components are the way to go yet some of the companies I have dealt with push the Amp's....any thoughts?
The biggest impact I heard was with my CD player. No difference with pre-amp and very little if any on power amp.

Point I forgot to mention - assuming there's a fixed budget and you could only add 1 "high-end" PC at a time....where would you add the PC and in what component order. On the digital side, I have put my Transport and DAC to the test and the DAC had a greater performance (sound) increase with the high end cable then that of the Transport. Components used were the following: Denon 2800 MKII, Bel Canto DAC, Wolff Carbon Sourse power cord.
The point is that you can buy ONE PC and switch it between ANY component of your rig.
Leave it where it bests to your taste and buy another one
Do the same with another one...
If you see no difference in performance at all leave stock ones and don't bother.
My experience with PCs has been transport first, then preamp. I think my two DACs (Cambridge IsoMagic, Apogee DA-100E) were unusual, because most often I have heard that the DAC is the first priority. For mine, though, very little difference.
It all comes down to the weakest link in your system and some power cords may work on one component but not as well on another. For example, I use an Elrod EPS Sig 3 that I like on my amp but not as much on my CDP, DAC or preamp. I also recently compared a power cord that was a cheaper one versus a higher price cable in a buddies system and mine. My cord in his system was out perfromed by his power cord but in my system, my power cord just sounded more real, go figure.

So as Marakanetz states, find or try out a well know power cord that sells used on Agon that you can resell for about the same money and try it out. There are plenty of people selling power cords these days that also offer a 30 day return policy.

Happy Listening.
don't forget there are PCs made specially for digital components