Televisions. For as much as six decades, the average "large" family room television had cost very roughly $700. But what you would get for $700 improved dramatically over that time, and the value of said $700 kept decreasing over time.
Yeah, I've paid double that for leading-edge TV's (e.g. 75" LED back in 2011), but the greater trend is the masses of 45" and 50" LED TV's that can now be had for $250 - $450... an amount most make in a single day. Your father probably had to save for weeks to buy a TV... for $700.
Computers are an even better example. I remember my father buying three computers in the mid-1980's, each close to $5k. Today, I buy $800 computers for my wife and kids, which work quite well for basic home chores. Even my high-end engineering workstations are under $10k... roughly $2k-$3k in mid-80's dollars, and these can do more calculations in a few seconds than my father's computers did in a full day.
