Okay, in-car technology has progressed somewhat since the 1950s, but I defy you to think of many more notable inventions in the history of car safety than that of the three-point seatbelt which celebrates its 50th anniversary today. Developed by Volvo engineer, Nils Bohlin the three-point belt was first introduced on Volvo's http://en.wikipedia.org/wiki/Volvo_PV444/544#PV544PV544 on 13 August 1959 and has saved an estimated on million plus lives since.
It's a credit to the significance of Bohlin's invention, therefore, that a better system has yet to be introduced. To Bohlin's (and Volvo's) particular credit, however, the patent for the three-point seatbelt was made available to other car manufacturers. Of course that freeing of his design is no doubt a contributing factor in the wide adoption of Bohlin's three-point belt, but the benefits are eminently self-evident.
Bohlin was also involved in developing a number of other safety features, such as Volvo's Side Impact Protection System (SIPS), but it's the three-point seat belt that has had the most impact - if you'll forgive the pun.
Indeed, while Bohlin's seatbelt wasn't the first - lapbelts had been around for years before - and almost certainly won't be the last it's undeniably the best solution available for now. Sure, multi-point harnesses can offer better protection in a crash but they're not exactly practical - as our good friends Misters Clarkson and Hammond have attested. I feel confident in predicting Bohlin's invention will have a place in vehicles for many years yet.