Nostalgia time for questions, what can you remember hearing or seeing in the past you just thought would never catch on?

When I was a kid, I remember the concept of bottled water came up and I thought for sure that would never fly; why would someone pay money for what you could get from the tap? Back when I was in college and expensive gas was considered to be $1.25 I thought if gas ever got to $3 bucks a gallon no one would go for it; they have, and then some. Back in the early 90s, when the Internet was blowing up, I had the chance to get in on the ground floor of an adult entertainment company. I passed, I was sure no one would spend $2 bucks a minute, to have some woman they could not see if she was pretty or not, talk dirty to them; boy was I wrong. What have you seen or heard of that you were sure no one would embrace it, or that it would never work, but it did?