As for the OP's comment about wires being "tires on the car", I could not disagree more. The speakers are ultimately where the rubber meets the road and the minuscule changes brought about by cables are often negated by them.
@jnorris2005 -- Actually, you and I completely agree. My analogy was meant to imply that you can build a Ferrari and optimize the engine, suspension, etc. (i.e. the more complicated stuff), but if you skimp on the tires it's all for naught. Similarly, if you go to the trouble of finding your ultimate source, preamp, amp, and speakers but connect them with cheap cables, you undermine the performance of all the goodness the speakers and electronics could otherwise provide.