As others have already stated, digital signals (such as HDMI or DVI) do not require expensive cables and you should be fine with a 3 foot cable of almost any quality, or longer cable of decent quality, but you don't need expensive Monster cables. The whole market for expensive "ultra" cables came about back during the audiophile years when people claimed they could hear a difference in their analog stereo signal using $100+ cables. While it did make some difference in analog signals on some high end systems, the difference was virtually indistinguishable to the average listener. It did make the person spending the money feel better about themselves, so the market thrived.
In short: No, you don't need those really expensive cables for a digital connection.