If you need an HDMI cable or HDMI-to-DVI cable to connect your PC to an HDTV, most of the retailers offer ridiculously overpriced solutions. Both HDMI and DVI cables deliver a digital signal, similar to the way USB or FireWire cables deliver digital signals. These are signals that can't be degraded by environmental interference because they are made up of binary data that's transmitted from the source (PC, PlayStation 3, HD-DVD player, etc) and displayed on the other end (the screen). The only scenario where the cable ceases to work is if it's damaged in some way.
The retailers like Best Buy, Circuit City, etc. still try to sell you an expensive cable, claiming that more shielding for the cabling will improve your image quality. This simply isn't true. The shielding makes no difference in the signal. The premium price for a 6-foot HDMI cable at Best Buy is $59.99 regularly according to the Website.
Instead of spending $60 on a 6-foot cable, you're better off shopping somewhere else. If you've got time to wait, Monoprice is among the best places to shop for cables online. A 6-foot HDMI cable from Monoprice is $17.93. The only difference is the cheaper cable doesn't come in one of those impossible to open blister packages. Even Apple avoids ripping off its customers with cables, offering a 2-meter cable for $20. A quick search of Amazon.com turns up numerous 6-foot HDMI cables priced under $20.
I'm not the only person who recognizes the HDMI rip-off. Opposable Thumbs just wrote up their own experience in shopping for HDMI cables. There's also a great article in the PS3 forums at Sony from an electrical engineer about why the expensive HDMI cables are no better than cheaper ones.
Bottom-line here: Just because you're spending $2000 on a television doesn't mean you need to overpay for a cable. Buy the $20 cable and get a couple of HD-DVDs to watch on that brand new screen, or buy two cables if you think cheaper somehow means lower quality. You'll still come out ahead.