I went to Wal-Mart the other day for some brake fluid for the Goggomobil (yeah, it's almost back on its wheels!) and noticed a stack of Haier air conditioners. Little window units, white steel and plastic, 5000 BTUs, $99. I stopped and looked a moment and was flung back nearly 40 years. I was moving into the fraternity house (TKE) at the University of Cincinnati for summer term (I was on the Section 2 co-op program schedule, so I worked Fall and Spring, and went to class Summer and Winter), and in anticipation of the usual hot and humid Ohio River Valley summer, went looking for an air conditioner. Sears had a store about a half mile from the campus, and was the likeliest source of such devices that I knew. And there they were, a stack of 5000 BTU window air conditioners, $100 each. They were off white (maybe almond) and had some fake wood trim, but were otherwise very like the Haier units at Wal-Mart. And the same price! After 40 years, these entry-level air conditioners are still selling for the same $100 price point! The Haier ones may well be better than the Sears units, at least in terms of efficiency and use of materials, perhaps performance too (I remember that our little overworked unit would occasionally completely encrust its coils with ice).
Such is the power of the market and the advance of technology. As a collector and student of early television technology, I am still amazed that the entry-level TV sets of the late 1940s sold for about the same number of dollars as TV sets today, nearly 60 years later. In about 1948 Pilot brought out the first TV set to sell for under $100. It had a 3-inch screen in a "portable" cabinet the size of a suitcase. Black and white of course. Today your $100 might buy a pocket-sized battery-powered LCD color TV of similar screen size, or half-a-dozen little monochrome CRT sets with 5- or 6-inch screens. The $200 price point is even more dramatic.
These examples of course just compare the dollar price, not the value. In 1968 that $100 was worth maybe 6 or 8 times what it is today, and the 1948 value would be 10 or 15 times greater. (These are my "gut feel" numbers, not a scientific measure of inflation. YMMV.) When I cringe a bit at the cost of a HDTV set, I stop and calculate what the then-new television technology cost in real terms back when I was a toddler and it seems much more reasonable.