Madhi19 Reddit new post madhi19 on What invention of the last 50 years would least impress the people of the 1700s?

Cars. "So you buy this mechanical Carriage, and it cost you how much? To keep it going you use oil lamp! And you change mechanical Carriage every five or six years!"

from overview for madhi19 http://www.reddit.com/r/AskReddit/comments/2kidis/what_invention_of_the_last_50_years_would_least/clm1yqp