We use You Tube TV for our TV programming. A few weeks back I was looking for some 0% Phos Copper brazing rods, couldn't find them locally, so bought them from an online plumbing supply at a good price with reasonable shipping. About a week later, there was an ad on TV from that same supply house. I thought it was a little out of the norm and suspected that not everyone was seeing that ad.
Last week I was Googling for a replacement spray nozzle for the tank sprayer. This morning there was a TV ad for a company that sells nozzles!
So, now I'm expecting the next thing I go searching for, a TV ad will come on that first calls me by my first name before it shows me the ad.

Coming from a marketing background, it's pretty cool this can be done. Coming from a personal security point of view, it's spooky.