Concorde
When I was a boy, I had a book. It featured the Transrapid (look it up!), the Shuttle, the Concorde ... as heralds of the future.The 2000s, when all of these things slowly were phased out, were a hard time, making me feel old for the first time. Sure, we got the Internet, we got vertically-landing rocket boosters, we got huge improvements in medical procedures ... but they all look so ... non-futuristic.