It was not that long ago that having a 50-inch screen, high-fidelity sound system and acoustically tuned theater in your home would qualify you for an appearance on Lifestyles of the Rich and Famous. These were the trappings of success, the toys of millionaires and Hollywood moguls. No longer. With the astounding progress made in the various technologies (monitors, projectors, speakers, acoustic treatments) and the dramatic price decreases, a complete home theater setup today would likely cost less than the first large-sized plasma screens. For the record, Philips sold the first 42-inch plasma TV model, in just four Sears locations, in 1997. The price tag? A cool 15 thousand bucks. A dozen years later, 42-inch TVs can be had for about $500.